A366685 a(n) = phi(11^n-1), where phi is Euler's totient function (A000010).

4, 32, 432, 3840, 64400, 373248, 7613424, 56217600, 765889344, 6913984000, 114117380608, 599824465920, 13796450740800, 98909341090560, 1356399209088000, 11341872916070400, 202178811399717504, 1171410130065973248, 24463636179365818512, 176391086415667200000

Offset

1,1

Links

Max Alekseyev, Table of n, a(n) for n = 1..316

Mathematica

EulerPhi[11^Range[30] - 1]

Prog

(PARI) {a(n) = eulerphi(11^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), this sequence (k=11), A366711 (k=12).

Cf. A000010, A024127, A366681, A366682, A366683, A366684.

Sequence in context: A222685 A322735 A140178 * A088991 A009668 A005121

Adjacent sequences: A366682 A366683 A366684 * A366686 A366687 A366688

Keyword

nonn

Author

Sean A. Irvine, Oct 16 2023

Status

approved