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A248626
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Least positive integer m such that prime(m+n) divides 2^m - 1.
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2
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3, 22, 18, 50, 48, 5, 48, 121, 390, 21, 37, 9, 11, 110, 672, 11628, 14, 286, 1000, 329, 15, 29, 32, 7, 90, 42, 1001, 816, 24, 408, 806, 6219, 761, 44, 75, 88, 30, 711, 16, 43, 2202, 110, 6112, 624, 12206, 590, 21, 156, 551, 525, 194, 64, 201, 225, 261, 1132, 305, 66, 500, 50
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OFFSET
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1,1
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COMMENTS
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Conjecture: a(n) exists for any n > 0.
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LINKS
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EXAMPLE
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a(2) = 22 since prime(22+2) = 89 divides 2^(22)-1 = 4194303 = 89*47127.
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MATHEMATICA
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Do[m=1; Label[aa]; If[Mod[2^m-1, Prime[m+n]]==0, Print[n, " ", m]; Goto[bb]]; m=m+1; Goto[aa]; Label[bb]; Continue, {n, 1, 60}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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