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 A340195 a(n) = Sum_{divisors d of n} A049559(d), where A049559(x) = gcd(phi(x), x-1). 3
 1, 2, 3, 3, 5, 5, 7, 4, 5, 7, 11, 7, 13, 9, 9, 5, 17, 8, 19, 9, 13, 13, 23, 9, 9, 15, 7, 13, 29, 13, 31, 6, 17, 19, 13, 11, 37, 21, 17, 11, 41, 17, 43, 15, 15, 25, 47, 11, 13, 12, 21, 19, 53, 11, 17, 15, 25, 31, 59, 17, 61, 33, 17, 7, 33, 25, 67, 21, 29, 19, 71, 14, 73, 39, 15, 25, 21, 21, 79, 13, 9, 43, 83, 23, 25, 45, 33 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 FORMULA a(n) = Sum_{d|n} A049559(d). a(n) = n - A340196(n). PROG (PARI) A049559(n) = gcd(eulerphi(n), n-1); A340195(n) = sumdiv(n, d, A049559(d)); CROSSREFS Inverse Möbius transform of A049559. Cf. A000010, A340196. Cf. also A340192. Sequence in context: A238527 A146071 A167411 * A340192 A112823 A247176 Adjacent sequences: A340192 A340193 A340194 * A340196 A340197 A340198 KEYWORD nonn AUTHOR Antti Karttunen, Jan 02 2021 STATUS approved

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Last modified December 7 15:01 EST 2022. Contains 358667 sequences. (Running on oeis4.)