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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

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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));