OFFSET
0,1
LINKS
Tyler Busby, Table of n, a(n) for n = 0..148 (terms 0..123 from Max Alekseyev)
Eric Weisstein's World of Mathematics, Sierpinski Number of the First Kind
MATHEMATICA
a[0] = 2; a[n_] := DivisorSigma[0, n^n + 1]; Array[a, 45, 0] (* Amiram Eldar, May 31 2021 *)
PROG
(PARI) a(n) = numdiv(n^n+1);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 31 2021
STATUS
approved