Stackexchange iconStackexchangeSep 9, 2026

A Novel Puzzle “Dewey’s Chexsum”

Consider the following sequence: 000000001 = 1 000000010 = 7 000000100 = 13 000001000 = 19 000010000 = 25 000100000 = 31 001000000 = 37 010000000 = 43 100000000 ≠ 49 So… 100000000 =?

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Consider the following sequence: 000000001 = 1 000000010 = 7 000000100 = 13 000001000 = 19 000010000 = 25 000100000 = 31 001000000 = 37 010000000 = 43 100000000 ≠ 49 So… 100000000 =?

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Consider the following sequence: 000000001 = 1 000000010 = 7 000000100 = 13 000001000 = 19 000010000 = 25 000100000 = 31 001000000 = 37 010000000 = 43 100000000 ≠ 49 So… 100000000 =? What number should replace the question mark, and why?

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What number should replace the question mark, and why?

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