A179671 - OEIS

%I #15 Jul 06 2020 05:58:26

%S 864,1944,4000,10976,25000,30375,42592,70304,83349,84375,134456,

%T 157216,219488,323433,389344,453789,533871,780448,953312,1071875,

%U 1193859,1288408,1620896,1666737,2100875,2205472,2544224,2956581,2970344,3322336,4159375,4348377

%N Products of the 5th power of a prime and a distinct prime of the 3rd power (p^5*q^3).

%H T. D. Noe, <a href="/A179671/b179671.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Pri#prime_signature">Index to sequences related to prime signature</a>

%F Sum_{n>=1} 1/a(n) = P(3)*P(5) - P(8) = A085541 * A085965 - A085968 = 0.002187..., where P is the prime zeta function. - _Amiram Eldar_, Jul 06 2020

%t f[n_]:=Sort[Last/@FactorInteger[n]]=={3,5}; Select[Range[10^6], f]

%Y Cf. A085541, A085965, A085968.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jul 23 2010