A078118 n+1 does not divide sigma(n!).

1, 6, 22, 25, 28, 30, 40, 42, 46, 52, 58, 60, 68, 70, 72, 78, 87, 88, 96, 98, 102, 105, 106, 112, 114, 122, 126, 128, 130, 133, 138, 145, 148, 150, 156, 162, 166, 172, 178, 182, 190, 192, 196, 198, 212, 213, 217, 218, 222, 225, 226, 228, 232, 238, 240, 250, 262

Offset: 1

Author

Benoit Cloitre, Dec 05 2002

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 1..8822
• Vaclav Kotesovec, Plot of a(n)/n for n = 1..8000

Crossrefs

Cf. A062569.

Programs

Mathematica

Select[Range[300], Not[Divisible[DivisorSigma[1, #!], # + 1]] &] (* Vaclav Kotesovec, Feb 16 2019 *)

Formula

a(n) seems to be asymptotic to c*n with c=4.8....