OFFSET
1,1
LINKS
Ray Chandler, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[2200], Mod[DivisorSigma[1, #], 4] == 3 &] (* Michael De Vlieger, Aug 10 2023 *)
PROG
(PARI) isok(n) = ((sigma(n) % 4) == 3); \\ Michel Marcus, Dec 19 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jun 19 2002
EXTENSIONS
Name edited by Michel Marcus, Dec 19 2013
STATUS
approved