A159034 Inverse Euler transform of A155200.

2, 7, 170, 16380, 6710886, 11453246035, 80421421917330, 2305843009213685760, 268650182136584261045760, 126765060022822940149666965093, 241677817415439249618874010960062650, 1858395433210885261794643189387357732203180, 57560679870263253393868202642364377389525958615670

Offset: 1

Author

Paul D. Hanna, Vladeta Jovovic, Apr 02 2009

Keywords

• easy
• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..50

Crossrefs

Cf. A155200.

Programs

Mathematica

Table[Sum[2^(d^2)*MoebiusMu[n/d], {d, Divisors[n]}]/n, {n, 1, 12}] (* Vaclav Kotesovec, Oct 09 2019 *)

PARI

a(n)={sumdiv(n, d, 2^(d^2)*moebius(n/d))/n} \\ Andrew Howroyd, Jan 08 2020

Formula

a(n) = (1/n)*Sum_{d|n} 2^(d^2)*moebius(n/d).

a(n) ~ 2^(n^2) / n. - Vaclav Kotesovec, Oct 09 2019

Extensions

Terms a(12) and beyond from Andrew Howroyd, Jan 08 2020