How to Count like a Mathematician Counting Warmup Round 1 squares - - PowerPoint PPT Presentation

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How to Count like a Mathematician Counting Warmup Round 1 squares - - PowerPoint PPT Presentation

How to Count like a Mathe- matician Lara Pudwell Introduction How to Count like a Mathematician Counting Warmup Round 1 squares Lara Pudwell dominoes Round 2 trees Department of Mathematics and Computer Science blocks The Bigger


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SLIDE 1

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

How to Count like a Mathematician

Lara Pudwell

Department of Mathematics and Computer Science

VERUM Seminar June 7, 2013

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SLIDE 2

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What do you research?

enumerative combinatorics

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SLIDE 3

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What do you research?

enumerative combinatorics counting things that are hard to count

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SLIDE 4

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

So you think you can count?

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, . . . 2, 4, 6, 8, 10, 12, 14, 16, 18, . . . 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, . . .

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SLIDE 5

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

So you think you can count?

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, . . . 2, 4, 6, 8, 10, 12, 14, 16, 18, . . . 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, . . . How many?

slide-6
SLIDE 6

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see?

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SLIDE 7

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 6 + 5 + 6

slide-8
SLIDE 8

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 6 + 5 + 6 = 17 Trick 1: Break your counting job into smaller jobs and add those results.

slide-9
SLIDE 9

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see?

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SLIDE 10

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 7 · 6

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SLIDE 11

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 7 · 6 = 42 Trick 2: Multiplying speeds things up!

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SLIDE 12

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see?

slide-13
SLIDE 13

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 7 · 6

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SLIDE 14

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

You’ve already got some tricks up your sleeve.... How many dots do you see? 7 · 6 − 3 42 − 3 = 39 Trick 3: Count a larger set and subtract off the extras.

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SLIDE 15

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways

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SLIDE 16

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways

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SLIDE 17

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways

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SLIDE 18

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways What’s the pattern?

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SLIDE 19

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways What’s the pattern? Count (end in ) + (end in ).

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SLIDE 20

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways What’s the pattern? Count (end in ) + (end in ). (end in ) = (end in ) = (lines with one less square).

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SLIDE 21

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways What’s the pattern? Count (end in ) + (end in ). (end in ) = (end in ) = (lines with one less square). Lines of length a = 2 × (lines of length a − 1)

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SLIDE 22

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white You have black squares and white squares . How many ways can you arrange a line of squares? 1 square? 2 ways 2 squares? 4 ways 3 squares? 8 ways What’s the pattern? Count (end in ) + (end in ). (end in ) = (end in ) = (lines with one less square). Lines of length a = 2 × (lines of length a − 1) length 1 2 3 4 5 6 7 8 # of arrangements 2 4 8 16 32 64 128 256

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SLIDE 23

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways

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SLIDE 24

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways 2 squares? 3 ways

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SLIDE 25

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways 2 squares? 3 ways 3 squares? 5 ways What’s the pattern?

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SLIDE 26

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways 2 squares? 3 ways 3 squares? 5 ways What’s the pattern? Count (end in ) + (end in ).

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SLIDE 27

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways 2 squares? 3 ways 3 squares? 5 ways What’s the pattern? Count (end in ) + (end in ). (end in ) = (end in ) = (lines with two less squares) (end in ) = (lines with one less square).

slide-28
SLIDE 28

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thinking in black and white What if you can’t have two black squares in a row? 1 square? 2 ways 2 squares? 3 ways 3 squares? 5 ways What’s the pattern? Count (end in ) + (end in ). (end in ) = (end in ) = (lines with two less squares) (end in ) = (lines with one less square). Lines of length a = (lines of length a − 2) + (lines of length a − 1) length 1 2 3 4 5 6 7 8 # of arrangements 2 3 5 8 13 21 34 55

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SLIDE 29

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Dominoes! You have a pile of dominoes . You wish to cover a rectangle of height 2 with non-overlapping dominoes. How many ways can this be done? 2 × 1 1 way

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SLIDE 30

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Dominoes! You have a pile of dominoes . You wish to cover a rectangle of height 2 with non-overlapping dominoes. How many ways can this be done? 2 × 1 1 way 2 × 2 2 ways

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SLIDE 31

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Dominoes! You have a pile of dominoes . You wish to cover a rectangle of height 2 with non-overlapping dominoes. How many ways can this be done? 2 × 1 1 way 2 × 2 2 ways 2 × 3 3 ways

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SLIDE 32

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Dominoes! You have a pile of dominoes . You wish to cover a rectangle of height 2 with non-overlapping dominoes. How many ways can this be done? 2 × 1 1 way 2 × 2 2 ways 2 × 3 3 ways 2 × 4 5 ways Hmmm....

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SLIDE 33

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Haven’t we met before? 2 3 5

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SLIDE 34

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Haven’t we met before? 2 3 5 Replace: → and → → → →

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SLIDE 35

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Haven’t we met before? 2 3 5 Replace: → and → → → → → → → ...then delete that last (white) box.

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SLIDE 36

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Trees?

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SLIDE 37

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Trees?

David Priscilla Kris Lara Ryan Dave Heather Amy Debbee Jennifer Lisa Jonathan Priscilla Rachel

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SLIDE 38

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Trees we can actually count... Trees grow down from the top of the page. Each node in a tree either has 0 children or 2 children. Nodes with 0 children are called leaves. This tree has 11 nodes. 6 of them are leaves.

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SLIDE 39

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree counting... leaves trees 1 1

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SLIDE 40

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree counting... leaves trees 1 1 2 1

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SLIDE 41

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree counting... leaves trees 1 1 2 1 3 2

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SLIDE 42

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree counting... leaves trees 1 1 2 1 3 2 4 5 leaves 1 2 3 4 5 trees 1 1 2 5 ?

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SLIDE 43

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Decomposing trees → ×

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SLIDE 44

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Decomposing trees... So for the 4 leaf trees... → × 3 left leaves, 1 right → × → × 2 left leaves, 2 right → × 1 left leaf, 3 right → ×

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SLIDE 45

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Decomposing trees... So for the 4 leaf trees... → × 3 left leaves, 1 right → × → × 2 left leaves, 2 right → × 1 left leaf, 3 right → × If Tn is the number of trees with n leaves... T4 = T3T1 + T2T2 + T1T3 = 2 · 1 + 1 · 1 + 1 · 2 = 2 + 1 + 2 = 5

slide-46
SLIDE 46

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree enumeration leaves 1 2 3 4 5 6 7 trees 1 1 2 5 ? ? ? T4 = T3T1 + T2T2 + T1T3 = 2 · 1 + 1 · 1 + 1 · 2 = 2 + 1 + 2 = 5

slide-47
SLIDE 47

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree enumeration leaves 1 2 3 4 5 6 7 trees 1 1 2 5 14 ? ? T4 = T3T1 + T2T2 + T1T3 = 2 · 1 + 1 · 1 + 1 · 2 = 2 + 1 + 2 = 5 Similarly... T5 = 5 · 1 + 2 · 1 + 1 · 2 + 1 · 5 = 14

slide-48
SLIDE 48

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree enumeration leaves 1 2 3 4 5 6 7 trees 1 1 2 5 14 42 ? T4 = T3T1 + T2T2 + T1T3 = 2 · 1 + 1 · 1 + 1 · 2 = 2 + 1 + 2 = 5 Similarly... T5 = 5 · 1 + 2 · 1 + 1 · 2 + 1 · 5 = 14 T6 = 14 · 1 + 5 · 1 + 2 · 2 + 1 · 5 + 1 · 14 = 42

slide-49
SLIDE 49

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Tree enumeration leaves 1 2 3 4 5 6 7 trees 1 1 2 5 14 42 132 T4 = T3T1 + T2T2 + T1T3 = 2 · 1 + 1 · 1 + 1 · 2 = 2 + 1 + 2 = 5 Similarly... T5 = 5 · 1 + 2 · 1 + 1 · 2 + 1 · 5 = 14 T6 = 14 · 1 + 5 · 1 + 2 · 2 + 1 · 5 + 1 · 14 = 42 T7 = 42 · 1 + 14 · 1 + 5 · 2 + 2 · 5 + 1 · 14 + 1 · 42 = 132

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SLIDE 50

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 3 2 1

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SLIDE 51

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 3 2 1

slide-52
SLIDE 52

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 3 2 1

slide-53
SLIDE 53

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 3 2 1

slide-54
SLIDE 54

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 2 3 1

slide-55
SLIDE 55

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 4 2 1 3

slide-56
SLIDE 56

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

5 2 4 1 3

slide-57
SLIDE 57

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

2 4 5 1 3

slide-58
SLIDE 58

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

2 4 1 3 5

slide-59
SLIDE 59

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

2 1 3 5 4

slide-60
SLIDE 60

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last game... Pile 1 is sorted (largest blocks at the bottom). Piles 2 and 3 can be in any order. You can move blocks from left to right. Question: How many possible arrangements can be made in Pile 3? Pile 1 Pile 2 Pile 3

1 3 5 4 2

One possible arrangement: 24531

slide-61
SLIDE 61

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting piles... 1

1

1

slide-62
SLIDE 62

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting piles... 1

1

1 2

1 2 1 2

2

slide-63
SLIDE 63

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting piles... 1

1

1 2

1 2 1 2

2 3

3 2 1 2 3 1 1 3 2 2 1 3 1 2 3

5

slide-64
SLIDE 64

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting piles... 1

1

1 2

1 2 1 2

2 3

3 2 1 2 3 1 1 3 2 2 1 3 1 2 3

5

1, 2, 5, . . .

slide-65
SLIDE 65

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting piles... 1

1

1 2

1 2 1 2

2 3

3 2 1 2 3 1 1 3 2 2 1 3 1 2 3

5

1, 2, 5, . . . (trees?)

slide-66
SLIDE 66

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

D` ej´ a vu?

1

slide-67
SLIDE 67

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

D` ej´ a vu?

1

→ Otherwise, locate the smallest block. Blocks above → left subtree. Blocks below → right subtree.

slide-68
SLIDE 68

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

D` ej´ a vu?

1

→ Otherwise, locate the smallest block. Blocks above → left subtree. Blocks below → right subtree.

1 2

1 2

slide-69
SLIDE 69

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

D` ej´ a vu?

1

→ Otherwise, locate the smallest block. Blocks above → left subtree. Blocks below → right subtree.

1 2

1 2

1 2 3 1 3 2 2 1 3 2 3 1 3 2 1

↓ ↓ ↓ ↓ ↓

slide-70
SLIDE 70

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last trick...

slide-71
SLIDE 71

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

One last trick...

slide-72
SLIDE 72

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What else is out there?

    1 1 1 −1 1 1    

slide-73
SLIDE 73

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Plane partitions

slide-74
SLIDE 74

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Plane partitions

slide-75
SLIDE 75

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Plane partitions

slide-76
SLIDE 76

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Plane partitions

slide-77
SLIDE 77

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Plane partitions

slide-78
SLIDE 78

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Counting problems!

1 3 5 4 2

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

slide-79
SLIDE 79

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Why?

slide-80
SLIDE 80

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What is it good for? G.H. Hardy (1877-1947)

“Hardy”, March 20, 2013 via http://www-groups.dcs.st-and.ac.uk/ ~history/PictDisplay/Hardy.html, public domain.

A Mathematician’s Apology (1940)

slide-81
SLIDE 81

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What is it good for? G.H. Hardy (1877-1947)

“Hardy”, March 20, 2013 via http://www-groups.dcs.st-and.ac.uk/ ~history/PictDisplay/Hardy.html, public domain.

A Mathematician’s Apology (1940) “No discovery of mine has made, or is likely to make... the least difference to the amenity of the world.”

slide-82
SLIDE 82

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

What is it good for?

“Impure Mathematics”, March 20, 2013 via http://abstrusegoose.com/504, Creative Commons Attribution-Noncommercial.

slide-83
SLIDE 83

How to Count like a Mathe- matician Lara Pudwell Introduction Counting Warmup Round 1

squares dominoes

Round 2

trees blocks

The Bigger Picture So what do you research?

Thanks for listening!