OFFSET
1,2
LINKS
FORMULA
MAPLE
A105824:= n-> (numtheory[sigma](n) mod 4):
seq (A105824(n), n=1..105); # Jani Melik, Jan 26 2011
MATHEMATICA
Table[Mod[DivisorSigma[1, n], 4], {n, 100}] (* Wesley Ivan Hurt, Nov 07 2017 *)
PROG
(PARI) a(n)=sigma(n)%4
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Shyam Sunder Gupta, May 05 2005
STATUS
approved