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 A144668 #12 Feb 16 2025 08:33:09
%S A144668 9,9,5,9,9,1,2,6,5,8,9,3,4,0,4,6,5,5,1,1,9,1,9,4,1,3,1,7,4,5,8,2,2,9,
%T A144668 3,0,8,5,6,6,2,2,6,6,6,2,5,0,3,5,5,0,4,9,7,5,3,4,3,9,9,7,1,9,6,3,6,6,
%U A144668 5,1,6,1,7,2,7,3,5,1,1,6,2,3,2,8,3,3,6,4,3,9,7,7,9,9,2,7,6,1,3,0,0,9,7,6,6
%N A144668 Decimal expansion of product_{n=2..infinity} (n^9-1)/(n^9+1).
%H A144668 J. Borwein et al., <a href="http://www.ams.org/mathscinet-getitem?mr=2051473">Experimentation in Mathematics</a>, 2004, section 1.2.
%H A144668 E. W. Weisstein, <a href="https://mathworld.wolfram.com/InfiniteProduct.html">Infinite Product</a>, MathWorld.
%e A144668 0.99599126589340465511919...
%t A144668 p = 2/3*Product[Gamma[2 + (-1)^(k + k/9)], {k, {1, 2, 4, 5, 7, 8}}]/ Product[Gamma[2 - (-1)^(k + k/9)], {k, {1, 2, 4, 5, 7, 8}}]; RealDigits[Re[p], 10, 105][[1]] (* _Jean-François Alcover_, Feb 11 2013, updated Nov 18 2015 *)
%Y A144668 Cf. A090986.
%K A144668 nonn,cons,easy
%O A144668 0,1
%A A144668 _R. J. Mathar_, Feb 01 2009
%E A144668 More terms from _Jean-François Alcover_, Feb 11 2013