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A280149
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Numbers k such that 3^k - 2^k is not squarefree.
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7
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10, 11, 20, 22, 30, 33, 40, 42, 44, 50, 52, 55, 57, 60, 66, 70, 77, 80, 84, 88, 90, 99, 100, 104, 110, 114, 120, 121, 126, 130, 132, 140, 143, 150, 154, 156, 160, 165, 168, 170, 171, 176, 180, 187, 190, 198, 200, 203, 208, 209, 210, 220, 228, 230, 231, 240, 242, 250, 252, 253, 260, 264, 270, 272, 275, 280, 285
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OFFSET
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1,1
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COMMENTS
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Numbers divisible by the order of 3/2 mod p^2 for some prime p > 3.
Includes numbers divisible by p^2-p for some prime p > 3.
If k is a member, then so are all multiples of k. (End)
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LINKS
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EXAMPLE
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10 is in this sequence because 3^10 - 2^10 = 58025 = 5^2*11*211.
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MATHEMATICA
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PROG
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(Magma) [n: n in [1..156] | not IsSquarefree(3^n-2^n)];
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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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