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

0,2

Links

Max Alekseyev, Table of n, a(n) for n = 0..420

Formula

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

Mathematica

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

Prog

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

Crossrefs

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

Cf. A053285, A366579, A366608, A366618, A366639, A366658, A366667, A366669, A366690, A366716.

Sequence in context: A294465 A074444 A348568 * A209904 A146883 A159721

Adjacent sequences: A366627 A366628 A366629 * A366631 A366632 A366633

Keyword

nonn

Author

Sean A. Irvine, Oct 14 2023

Status

approved