login
A366630
a(n) = phi(6^n+1), where phi is Euler's totient function (A000010).
11
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
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)}
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 14 2023
STATUS
approved