This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A065481 #13 Mar 15 2021 03:42:09
%S A065481 3,8,8,9,4,5,1,8,9,9,7,9,5,6,1,9,2,9,3,1,1,5,7,8,7,8,9,7,6,4,4,5,0,9,
%T A065481 1,2,6,7,6,5,4,4,9,5,4,2,7,5,6,9,5,8,6,4,7,4,1,4,3,2,0,9,8,3,7,0,0,3,
%U A065481 9,1,2,3,3,1,9,1,7,9,0,3,2,8,0,9,7,9,7,2,7,7,5,9,6,0,8,6,9,1
%N A065481 Decimal expansion of Product_{p prime} (1 - 1/(p^2-2)).
%H A065481 G. Niklasch, <a href="/A001692/a001692.html">Some number theoretical constants: 1000-digit values</a>. [Cached copy]
%e A065481 0.38894518997956192931157878976445...
%t A065481 $MaxExtraPrecision = 2000; digits = 98; terms = 2000; P[n_] := PrimeZetaP[n ]; LR = LinearRecurrence[{0, 5, 0, -6}, {0, 0, -2, 0}, terms + 10]; r[n_Integer] := LR[[n]]; Exp[NSum[r[n]*P[n - 1]/(n - 1), {n, 3, terms}, NSumTerms -> terms, WorkingPrecision -> digits + 10]] // RealDigits[#, 10, digits]& // First (* _Jean-François Alcover_, Apr 18 2016 *)
%o A065481 (PARI) prodeulerrat(1 - 1/(p^2-2)) \\ _Amiram Eldar_, Mar 15 2021
%Y A065481 Cf. A065178, A078076.
%K A065481 cons,nonn
%O A065481 0,1
%A A065481 _N. J. A. Sloane_, Nov 19 2001