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 A349555 a(n) = Sum_{p<=n, p prime} p^floor(1/gcd(n/p)). 0

%I

%S 0,1,3,4,6,7,11,16,15,12,18,25,29,34,35,40,42,55,59,72,69,66,78,97,96,

%T 87,98,93,101,122,130,159,148,143,150,157,161,178,183,192,198,229,239,

%U 270,275,258,282,325,322,323,310,315,329,378,367,374,361,352,382,433,441,470

%N a(n) = Sum_{p<=n, p prime} p^floor(1/gcd(n/p)).

%C For each prime number p less than or equal to n, add 1 if p|n, otherwise add p (see example).

%F a(n) = A001221(n) + A066911(n).

%e a(9) = 15; The primes less than or equal to 9 are 2, 3, 5, 7 and only 3|9. We then have, respectively, a(9) = 2 + 1 + 5 + 7 = 15.

%t nterms=100;Table[Total[Map[If[Mod[n,#]==0,1,#]&,Prime[Range[PrimePi[n]]]]],{n,nterms}] (* _Paolo Xausa_, Nov 22 2021 *)

%Y Cf. A001221, A066911.

%K nonn

%O 1,3

%A _Wesley Ivan Hurt_, Nov 21 2021

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Last modified March 27 18:55 EDT 2023. Contains 361575 sequences. (Running on oeis4.)