A366630 a(n) = phi(6^n+1), where phi is Euler's totient function (A000010).

1, 6, 36, 180, 1296, 6000, 41472, 230496, 1580800, 8359200, 58579200, 310968900, 2175102720, 10971642240, 76065091200, 351048600000, 2811459796992, 14508487949472, 88870766837760, 522016066337712, 3564233663616000, 17479898551382400, 128060205344805888

Offset: 0

Author

Sean A. Irvine, Oct 14 2023

Keywords

• nonn

Links

• Max Alekseyev, Table of n, a(n) for n = 0..430

Crossrefs

Cf. A062394, A000010, A366623, A366618, A366627, A366628, A366629, A366670.

Cf. A053285, A366579, A366608, A366639, A366658, A366667, A366669, A366690, A366716.

Programs

Mathematica

EulerPhi[6^Range[0, 22] + 1] (* Paul F. Marrero Romero, Oct 17 2023 *)

PARI

{a(n) = eulerphi(6^n+1)}

Formula

a(n) = A000010(A062394(n)). - Paul F. Marrero Romero, Oct 17 2023