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A366711
a(n) = phi(12^n-1), where phi is Euler's totient function (A000010).
13
10, 120, 1560, 13440, 226200, 2021760, 32518360, 274391040, 4534807680, 51953616000, 646094232960, 4662793175040, 97266341877120, 1070382142166400, 13666309113600000, 109897747141754880, 2016918439151095000, 17518491733377024000, 290436363064202660760
OFFSET
1,1
LINKS
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).
Sequence in context: A027568 A318495 A320760 * A034255 A363310 A051582
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 17 2023
STATUS
approved