OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..6287
FORMULA
MATHEMATICA
rad[n_] := Times @@ FactorInteger[n][[;; , 1]]; a[n_] := DivisorSum[n, rad[#]^(n / #) &]; Array[a, 50] (* Amiram Eldar, Sep 07 2020 *)
PROG
(PARI) {a(n)=sumdiv(n, d, prod(i=1, omega(d), factor(d)[i, 1])^(n/d))} /* also formed by the log of G094947(x): */ {a(n)=n*polcoeff(sum(k=1, n, -log(1-prod(i=1, omega(k), factor(k)[i, 1])*x^k+x*O(x^n))/k), n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, May 26 2004
STATUS
approved