A073575 Sum of factorial numbers dividing n.

1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 33, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 33, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 33, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 9, 1, 3, 1, 3, 1, 33, 1, 3, 1, 3, 1, 9

Offset: 1

Author

Vladeta Jovovic, Aug 27 2002

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10079

Crossrefs

Cf. A000142, A007489, A055770, A055881, A007489.

Programs

Mathematica

Table[Total[Select[Table[i!, {i, n}], Divisible[n, #] &]], {n, 102}] (* Jayanta Basu, Jul 01 2013 *)

PARI

A073575(n) = { my(m=1, i=2, s=0); while(!(n%m), s += m; m *= i; i++); return(s); } \\ Antti Karttunen, Dec 19 2018

Formula

G.f.: Sum_{k>0} k!*x^(k!)/(1-x^(k!)). - Vladeta Jovovic, Dec 13 2002

a(n) = A007489(A055881(n)). - Antti Karttunen, Dec 19 2018