OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[60000], DivisorSigma[1, #]^2>9DivisorSigma[2, #]&] (* Harvey P. Dale, Mar 20 2015 *)
PROG
(PARI) for(n=1, 1000, if(sigma(n)^2>9*sumdiv(n, k, k^2), print1(n, ", ")))
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 04 2002
STATUS
approved