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Search: id:A112643
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A112643 Odd and square-free abundant numbers. +0
4
15015, 19635, 21945, 23205, 25935, 26565, 31395, 33495, 33915, 35805, 39585, 41055, 42315, 42735, 45885, 47355, 49665, 50505, 51765, 54285, 55965, 58695, 61215, 64155, 68145, 70455, 72345, 77385, 80535, 82005, 83265, 84315, 91245 (list; graph; listen)
OFFSET

1,1

COMMENT

Deviates from A046391.

EXAMPLE

199815=3.5.7.11.173

MATHEMATICA

ta={{0}}; Do[g=n; s=DivisorSigma[1, n]-2*n; If[Greater[s, 0]&&Equal[Abs[MoebiusMu[n]], 1]&& !Equal[Mod[n, 2], 0], Print[n, PrimeFactorList[n], s]; ta=Append[ta, n]], {n, 1, 200000}]; {ta=Delete[ta, 1], g}

CROSSREFS

Cf. A087248, A046391.

Adjacent sequences: A112640 A112641 A112642 this_sequence A112644 A112645 A112646

Sequence in context: A081635 A104875 A046391 this_sequence A129485 A133778 A124047

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Sep 20 2005

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Last modified October 11 13:47 EDT 2008. Contains 144830 sequences.


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