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A322581
Sum of A003958 and its Dirichlet inverse: a(n) = A003958(n) + A097945(n).
9
2, 0, 0, 1, 0, 4, 0, 1, 4, 8, 0, 2, 0, 12, 16, 1, 0, 4, 0, 4, 24, 20, 0, 2, 16, 24, 8, 6, 0, 0, 0, 1, 40, 32, 48, 4, 0, 36, 48, 4, 0, 0, 0, 10, 16, 44, 0, 2, 36, 16, 64, 12, 0, 8, 80, 6, 72, 56, 0, 8, 0, 60, 24, 1, 96, 0, 0, 16, 88, 0, 0, 4, 0, 72, 32, 18, 120, 0, 0, 4, 16, 80, 0, 12, 128, 84, 112, 10, 0, 16, 144, 22, 120, 92, 144
OFFSET
1,1
LINKS
FORMULA
a(n) = A003958(n) + A097945(n).
MATHEMATICA
a[1] = 2; a[n_] := Times @@ ((First[#] - 1)^Last[#] & /@ FactorInteger[n]) + MoebiusMu[n] * EulerPhi[n]; Array[a, 60] (* Amiram Eldar, Dec 17 2018 *)
PROG
(PARI)
A003958(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1]--); factorback(f); };
A097945(n) = (moebius(n)*eulerphi(n));
A322581(n) = (A003958(n)+A097945(n));
CROSSREFS
Cf. also A319340.
Sequence in context: A349126 A340188 A323911 * A347083 A209915 A349386
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 17 2018
STATUS
approved