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Decimal expansion of Sum_{primes p} 1/(p^2*(p-1)).
4

%I #17 Mar 18 2021 07:29:34

%S 3,2,0,9,0,9,2,4,9,0,0,8,7,2,9,6,2,9,3,5,7,8,2,4,0,9,5,0,2,3,6,9,4,4,

%T 6,1,4,4,5,5,0,9,9,9,2,8,4,3,2,9,3,6,2,6,5,7,4,5,8,7,1,3,7,0,0,5,5,4,

%U 4,0,0,1,1,2,5,3,2,2,5,2,3,3,8,4,8,4,1,2,1,4,4,6,8,4,1,3,9,6,0,1,0,6,1,3

%N Decimal expansion of Sum_{primes p} 1/(p^2*(p-1)).

%C Generally, sum_p 1/(p^s*(p-1)) equals A136141 minus the sum over all prime zeta functions with index 2 to s (see A085964 to A085969).

%F Equals A136141 minus A085548 .

%F Equals Sum_{n>=1} 1/A246549(n). - _Amiram Eldar_, Oct 27 2020

%e 0.320909249008729629357824095023694461445509992843293626574587137005544001125... = 1/(4*1) + 1/(9*2) + 1/(25*4) + 1/(49*6) + ...

%t digits = 104; sp = NSum[PrimeZetaP[n], {n, 3, Infinity}, WorkingPrecision -> digits + 10, NSumTerms -> 2*digits]; RealDigits[sp, 10, digits] // First (* _Jean-François Alcover_, Sep 11 2015 *)

%o (PARI) sumeulerrat(1/(p^2*(p-1))) \\ _Amiram Eldar_, Mar 18 2021

%Y Cf. A085548, A136141, A246549.

%K cons,nonn

%O 0,1

%A _R. J. Mathar_, Dec 04 2008

%E More digits from _Jean-François Alcover_, Sep 11 2015