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A073575
Sum of factorial numbers dividing n.
3
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
1,2
LINKS
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
MATHEMATICA
Table[Total[Select[Table[i!, {i, n}], Divisible[n, #] &]], {n, 102}] (* Jayanta Basu, Jul 01 2013 *)
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Aug 27 2002
STATUS
approved