How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x...

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Transcript of How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x...

Page 1: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.
Page 2: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

How many squares on a chessboard?

Clue 1

1 x 1 = 64

2 x 2 = 49

3 x 3 = 36

4 x 4 = 25

5 x 5 = 16

6 x 6 = 9

7 x 7 = 4

8 x 8 = 1

12 + 22 + 32 + 42 + 52 + 62 + 72 + 82 = 204

204

There isn’t a clue 2.

Page 3: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

You may be familiar with the formula that adds up successive whole numbers.

There is also a formula for adding successive square numbers.

2 2 ( 1)(2 1) (1 )

6n n n

Sum n

2 2 8 9 17 (1 8 ) 204

6x x

Sum

Research a formula that adds up successive cube numbers.

Check that it works for the chessboard problem.

How is it

Derived?.

( 1) (1 )

2n n

Sum n

How is it

Derived?.

Page 4: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

A Knights Tour

Page 5: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

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A Knights Tour of a 6 x 6 Chessboard

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Page 6: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

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A Knights Tour of a 6 x 6 Chessboard

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Page 7: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

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Page 8: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.
Page 9: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

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A Knights Tour of an 8 x 8 Chessboard

De Moivre’s Solution

Page 10: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

A Knights Tour of an 8 x 8 Chessboard

Euler’s Magic Square Solutio

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What’s the

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Page 11: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.

A Knights Tour of an 8 x 8 Chessboard

Euler’s re-entrant half-board Solution

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Page 12: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.
Page 13: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.
Page 14: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.
Page 15: How many squares on a chessboard? Clue 1 1 x 1 = 64 2 x 2 = 49 3 x 3 = 36 4 x 4 = 25 5 x 5 = 16 6 x 6 = 9 7 x 7 = 4 8 x 8 = 1 1 2 + 2 2 + 3 2 + 4 2.