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A074696
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Numbers k such that 2^k+1 has more than k divisors (k such that A000005(2^k+1) > k).
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1
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0, 1, 30, 42, 45, 50, 54, 63, 70, 75, 78, 81, 90, 99, 102, 105, 114, 118, 126, 130, 135, 138, 150, 153, 154, 162, 165, 168, 170, 171, 174, 175, 177, 180, 182, 186, 189, 190, 194, 195, 196, 198, 204, 210, 216, 220, 222, 225, 228, 230, 231, 234, 238
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OFFSET
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1,3
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LINKS
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MATHEMATICA
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Select[Range[0, 150], DivisorSigma[0, 2^#+1] > # &] (* Amiram Eldar, May 10 2022 *)
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PROG
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(PARI) isok(n) = numdiv(2^n+1) > n; \\ Michel Marcus, Nov 29 2013
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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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