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 A034760 Dirichlet convolution of primes (with 1) with phi(n). 1
 1, 3, 5, 9, 11, 20, 19, 30, 31, 42, 39, 66, 49, 72, 77, 90, 69, 124, 79, 140, 127, 132, 101, 208, 137, 170, 175, 224, 135, 292, 143, 260, 239, 238, 257, 396, 187, 272, 297, 428, 213, 478, 223, 412, 445, 342, 245, 604, 343, 496, 415, 512, 291, 636, 477, 674, 475 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..57. FORMULA From Richard L. Ollerton, May 06 2021: (Start) a(n) = Sum_{d|n} A000010(d)*A008578(n/d) (by definition). a(n) = Sum_{k=1..n} A008578(gcd(n,k)). a(n) = Sum_{k=1..n} A008578(n/gcd(n,k))*A000010(gcd(n,k))A000010(n/gcd(n,k)). (End) PROG (PARI) pbc(n) = if (n==1, 1, prime(n-1)); a(n) = sumdiv(n, d, pbc(d)*eulerphi(n/d)); \\ Michel Marcus, Feb 28 2019 CROSSREFS Cf. A000010, A008578. Sequence in context: A212288 A213208 A282098 * A070639 A078392 A364808 Adjacent sequences: A034757 A034758 A034759 * A034761 A034762 A034763 KEYWORD nonn AUTHOR Erich Friedman STATUS approved

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Last modified February 25 17:36 EST 2024. Contains 370332 sequences. (Running on oeis4.)