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A231563
a(n) = f(1)^n + ... + f(n)^n (mod n) where f(i)=i if gcd(i,n)=1 and f(i)=0 otherwise.
5
0, 1, 0, 2, 0, 2, 0, 4, 0, 0, 0, 4, 0, 0, 0, 8, 0, 6, 0, 8, 0, 0, 0, 8, 0, 0, 0, 0, 0, 20, 0, 16, 0, 0, 0, 12, 0, 0, 0, 16, 0, 12, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 18, 0, 0, 0, 0, 0, 16, 0, 0, 0, 32, 0, 44, 0, 0, 0, 0, 0, 24, 0, 0, 0, 0, 0, 0, 0, 32, 0, 0
OFFSET
1,4
LINKS
FORMULA
a(n) = A308481(n) mod n. - Seiichi Manyama, Feb 11 2021
MATHEMATICA
S[n_] := Mod[Sum[If[GCD[i, n] == 1, PowerMod[i, n, n], 0], {i, 1, n}], n]; Array[S, 100]
PROG
(PARI) f(i, n) = if (gcd(i, n) == 1, i, 0);
a(n) = lift(sum(k=1, n, Mod(f(k, n), n)^n)); \\ Michel Marcus, Jul 16 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved