OFFSET
1,4
LINKS
FORMULA
a(n) = 2*A001065(n) - 1. - Antti Karttunen, Oct 30 2017
MATHEMATICA
Array[2 (DivisorSigma[1, #] - # - 1) + 1 &, 87] (* Michael De Vlieger, Oct 30 2017 *)
PROG
(PARI) j=[]; for(n=1, 200, j=concat(j, 2*(sigma(n)-n-1)+1)); j
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Jason Earls, Jul 23 2001
STATUS
approved