OFFSET
1,2
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Florian Luca and John Ferdinands, Problem 11090: Sometimes n divides sigma_k(n), Amer. Math. Monthly 113:4 (2006), pp. 372-373.
MATHEMATICA
Do[If[Mod[DivisorSigma[9, n], n]==0, Print[n]], {n, 1, 5000}]
PROG
(PARI) is(n)=sigma(n, 9)%n==0 \\ Charles R Greathouse IV, Feb 04 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jun 09 2000
STATUS
approved