A073413 Numbers n such that number of divisors of n divides S(n), the Kempner function A002034.

1, 2, 8, 9, 18, 45, 128, 243, 486, 625, 1215, 1250, 1701, 1875, 2673, 3750, 4375, 5000, 6561, 6875, 8125, 8750, 10625, 11875, 13122, 13125, 13750, 16250, 16875, 20625, 21250, 23750, 24375, 31875, 32768, 32805, 35625, 45927, 48125, 56875, 72171, 74375, 83125

Offset

1,2

Links

Table of n, a(n) for n=1..43.

Mathematica

S[n_] := Block[{k = 1}, While[ ! IntegerQ[k!/n], k++ ]; k]; Do[ If[ IntegerQ[ S[n]/DivisorSigma[0, n]], Print[n]], {n, 1, 3000}]

Crossrefs

Cf. A000005, A002034, A073331, A073535.

Sequence in context: A126160 A118962 A096033 * A046681 A259672 A163619

Adjacent sequences: A073410 A073411 A073412 * A073414 A073415 A073416

Keyword

nonn

Author

Jason Earls, Aug 23 2002

Extensions

More terms from Robert G. Wilson v, Aug 25 2002

More terms from Amiram Eldar, Jan 28 2019

Status

approved