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%I #24 Sep 08 2020 06:12:15
%S 5,3,5,8,9,6,1,5,3,8,2,8,3,3,7,9,9,9,8,0,8,5,0,2,6,3,1,3,1,8,5,4,5,9,
%T 5,0,6,4,8,2,2,2,3,7,4,5,1,4,1,4,5,2,7,1,1,5,1,0,1,0,8,3,4,6,1,3,3,2,
%U 8,8,1,1,9,6,1,4,5,4,1,1,0,4,5,1,1,4,4,6,5,8,2,7,3,1,0,0,2,3,4,4,0,5,3,5,1,1
%N Decimal expansion of Product_{primes p} (1 - 1/p^2 - 1/p^3 + 1/p^4).
%F Equals (6/Pi^2) * A065465. - _Amiram Eldar_, Sep 08 2020
%e 0.5358961538283379998085026313185459506482223745141452711510108346133288119...
%t Do[Print[N[Exp[-Sum[q = Expand[(p^2 + p^3 - p^4)^j]; Sum[PrimeZetaP[Exponent[q[[k]], p]] * Coefficient[q[[k]], p^Exponent[q[[k]], p]], {k, 1, Length[q]}]/j, {j, 1, t}]], 50]], {t, 10, 100, 10}]
%o (PARI) (6/Pi^2) * prodeulerrat(1 - 1/(p^2*(p+1))) \\ _Amiram Eldar_, Sep 08 2020
%Y Cf. A055653, A062354, A065465, A175639, A256392, A332713.
%K nonn,cons
%O 0,1
%A _Vaclav Kotesovec_, Dec 17 2019