A377674 - OEIS

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A377674

a(n) = phi(n^n + n) where phi is the Euler totient function.

1, 2, 8, 96, 1248, 12000, 259200, 5461344, 129140160, 2725643520, 127561104000, 2743415522496, 139778722137600, 2504616361228800, 111747349423990784, 8644660582219776000, 387774574486565683200, 12306643656809728412160, 816897235219321957908480

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..116

FORMULA

a(n) = A000010(A066068(n)).

MATHEMATICA

a[n_] := EulerPhi[n^n + n]; Array[a, 20] (* Amiram Eldar, Nov 04 2024 *)

PROG

(PARI) a(n) = eulerphi(n^n+n);

CROSSREFS