A034760 Dirichlet convolution of primes (with 1) with phi(n).

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

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