OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..348
Eric Weisstein's World of Mathematics, Abundance
MATHEMATICA
Select[Range[15000], Divisible[#, DivisorSigma[1, #]-2#]&]//Quiet (* Harvey P. Dale, Mar 15 2018 *)
PROG
(PARI) is(n)=my(t=sigma(n)-2*n); t && n%t==0 \\ Charles R Greathouse IV, Dec 12 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 24 2004
STATUS
approved