A325385 a(n) = gcd(n-A048250(n), n-A162296(n)).

1, 1, 1, 1, 1, 6, 1, 1, 5, 2, 1, 4, 1, 2, 3, 1, 1, 3, 1, 2, 1, 2, 1, 12, 19, 2, 1, 4, 1, 6, 1, 1, 3, 2, 1, 1, 1, 2, 1, 2, 1, 6, 1, 4, 3, 2, 1, 4, 41, 1, 3, 2, 1, 6, 1, 8, 1, 2, 1, 12, 1, 2, 1, 1, 1, 6, 1, 2, 3, 2, 1, 3, 1, 2, 1, 4, 1, 6, 1, 2, 1, 2, 1, 4, 1, 2, 3, 4, 1, 18, 7, 4, 1, 2, 5, 12, 1, 1, 3, 1, 1, 6, 1, 2, 3

Offset: 1

Author

Antti Karttunen, Apr 24 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537

Crossrefs

Cf. A048250, A126795, A162296, A228058, A325313, A325314, A325375.

Programs

PARI

A048250(n) = factorback(apply(p -> p+1,factor(n)[,1]));
A162296(n) = sumdiv(n, d, d*(1-issquarefree(d)));
A325385(n) = gcd(n-A048250(n),n-A162296(n));

Formula

a(n) = gcd(n-A048250(n), n-A162296(n)).

a(n) = gcd(A325313(n), A325314(n)).

a(A228058(n)) = A325375(n).