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A073081
Greatest k such that k! divides sigma(n!).
1
1, 1, 3, 3, 5, 3, 4, 6, 6, 2, 4, 4, 4, 7, 7, 7, 7, 4, 9, 7, 8, 8, 11, 8, 8, 10, 10, 9, 10, 13, 14, 13, 6, 10, 10, 10, 10, 10, 10, 12, 12, 12, 12, 12, 12, 8, 11, 11, 12, 19, 21, 16, 16, 16, 14, 14, 12, 16, 16, 16, 16, 16, 16, 22, 21, 21, 21, 19, 19, 20, 20, 20, 20, 22, 21, 21, 19, 14
OFFSET
1,3
COMMENTS
sum(k=1,n,a(k)) seems to be asymptotic to C*n^2 with 1/20 < C < 1/10.
LINKS
PROG
(PARI) a(n) = my(m=1, s=sigma(n!)); for (k=1, n, if ((s % k!) == 0, m = max(m, k))); m; \\ Michel Marcus, Dec 05 2019
CROSSREFS
Cf. A062569 (sigma(n!)).
Sequence in context: A359421 A014780 A216199 * A094928 A178984 A065507
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Aug 17 2002
STATUS
approved