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A340143
Möbius transform of A160595, where A160595(x) = phi(x)/gcd(phi(x), x-1).
5
1, 0, 0, 1, 0, 1, 0, 2, 2, 3, 0, 1, 0, 5, 3, 4, 0, 2, 0, 3, 2, 9, 0, 2, 4, 11, 6, -3, 0, 0, 0, 8, 4, 15, 11, 4, 0, 17, 11, 6, 0, 3, 0, 9, 0, 21, 0, 4, 6, 12, 15, -5, 0, 6, 19, 18, 8, 27, 0, 3, 0, 29, 13, 16, 2, -11, 0, 15, 10, -12, 0, 8, 0, 35, 12, -7, 14, 0, 0, 12, 18, 39, 0, 13, 15, 41, 27, 18, 0, 12, 3, 21, 14, 45, 35
OFFSET
1,8
FORMULA
a(n) = Sum_{d|n} A008683(n/d) * A160595(d).
MATHEMATICA
Table[DivisorSum[n, MoebiusMu[n/#1]*#2/GCD[#2, #3] & @@ {#, EulerPhi[#], # - 1} &], {n, 95}] (* Michael De Vlieger, Dec 29 2020 *)
PROG
(PARI)
A160595(n) = { my(x=eulerphi(n)); x/gcd(x, n-1); };
A340143(n) = sumdiv(n, d, moebius(n/d)*A160595(d));
CROSSREFS
Cf. also A340141, A340142.
Sequence in context: A073438 A187096 A340146 * A255920 A160115 A139365
KEYWORD
sign
AUTHOR
Antti Karttunen, Dec 29 2020
STATUS
approved