A366711 a(n) = phi(12^n-1), where phi is Euler's totient function (A000010).

10, 120, 1560, 13440, 226200, 2021760, 32518360, 274391040, 4534807680, 51953616000, 646094232960, 4662793175040, 97266341877120, 1070382142166400, 13666309113600000, 109897747141754880, 2016918439151095000, 17518491733377024000, 290436363064202660760

Offset

1,1

Links

Max Alekseyev, Table of n, a(n) for n = 1..310

Mathematica

EulerPhi[12^Range[30] - 1]

Prog

(PARI) {a(n) = eulerphi(12^n-1)}

Crossrefs

phi(k^n-1): A053287 (k=2), A295500 (k=3), A295501 (k=4), A295502 (k=5), A366623 (k=6), A366635 (k=7), A366654 (k=8), A366663 (k=9), A295503 (k=10), A366685 (k=11), this sequence (k=12).

Cf. A000010, A024140, A366707, A366708, A366709, A366710, A366717, A366718.

Sequence in context: A027568 A318495 A320760 * A034255 A363310 A051582

Adjacent sequences: A366708 A366709 A366710 * A366712 A366713 A366714

Keyword

nonn

Author

Sean A. Irvine, Oct 17 2023

Status

approved