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A280302
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Smallest k such that (n+1)^k - n^k is divisible by a square > 1.
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10
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6, 10, 4, 2, 21, 20, 3, 20, 33, 6, 20, 2, 2, 5, 21, 6, 10, 6, 6, 4, 4, 2, 7, 2, 6, 3, 10, 4, 18, 6, 2, 10, 20, 6, 57, 17, 2, 14, 42, 2, 10, 10, 6, 39, 14, 4, 10, 20, 2, 21, 20, 6, 4, 21, 6, 20, 10, 2, 5, 2, 5, 2, 20, 6, 42, 14, 2, 6, 55, 6, 3, 7, 2, 42, 3, 2
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OFFSET
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1,1
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COMMENTS
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a(209) > 70.
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LINKS
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EXAMPLE
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a(1) = 6 is because (1+1)^6 - 1^6 = 63 is divisible by 9 = 3^2.
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PROG
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(PARI) a(n) = {my(k = 1); while (issquarefree((n+1)^k - n^k), k++); k; } \\ Michel Marcus, Jan 14 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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