A343114 a(n) = Sum_{i=1..n} gcd(n^i,i).

1, 3, 5, 8, 9, 17, 13, 20, 21, 35, 21, 50, 25, 49, 51, 48, 33, 91, 37, 88, 77, 89, 45, 126, 65, 107, 81, 124, 57, 255, 61, 112, 141, 163, 137, 242, 73, 177, 167, 232, 81, 365, 85, 220, 227, 209, 93, 328, 133, 315, 213, 264, 105, 393, 229, 342, 257, 267, 117, 680, 121, 281

Offset: 1

Author

Wesley Ivan Hurt, Apr 05 2021

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A018804 (Pillai's function), A342449.

Programs

Mathematica

Table[Sum[GCD[n^i, i], {i, n}], {n, 100}]

PARI

a(n) = sum(i=1, n, gcd(n^i, i)); \\ Michel Marcus, Apr 05 2021

Formula

If p is prime, a(p) = 2*p -1. - Seiichi Manyama, Apr 06 2021