OFFSET
1,2
FORMULA
a(p) = p + 1 for primes p since we have 1^(1') + p^(p') = 1^0 + p^1 = p + 1.
EXAMPLE
a(4) = 259; a(4) = 1^(1') + 2^(2') + 4^(4') = 1^0 + 2^1 + 4^4 = 1 + 2 + 256 = 259.
PROG
(PARI) ad(n) = vecsum([n/f[1]*f[2]|f<-factor(n+!n)~]); \\ A003415
a(n) = sumdiv(n, d, d^ad(d)); \\ Michel Marcus, Oct 10 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Oct 09 2021
STATUS
approved