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 A269992 #14 Feb 01 2021 03:08:47
%S A269992 1,2,5,5,2,2,1,1,3,4,3,2,9,8,4,8,6,0,3,1,4,0,2,6,6,7,2,7,4,4,0,3,3,6,
%T A269992 0,1,5,6,0,5,4,3,5,7,0,4,4,4,4,3,0,0,3,8,3,6,8,8,7,0,6,2,4,1,4,9,3,0,
%U A269992 9,6,6,8,6,0,2,5,3,8,6,3,0,8,6,8,9,0
%N A269992 Decimal expansion of Sum_{n>=1} 2^(1-n)/L(n), where L = A000032 (Lucas numbers).
%F A269992 Equals Sum_{n>=1} 1/A084057(n) = 2 * Sum_{n>=1} 1/A087131(n). - _Amiram Eldar_, Feb 01 2021
%e A269992 1.2552211343298486031402667274403360...
%t A269992 x = N[Sum[2^(1 - n)/LucasL[n], {n, 1, 500}], 100]
%t A269992 RealDigits[x][[1]]
%o A269992 (PARI) L(n) = real((2 + quadgen(5)) * quadgen(5)^n); \\ A000032
%o A269992 suminf(n=1, 2^(1-n)/L(n)) \\ _Michel Marcus_, Nov 17 2020
%Y A269992 Cf. A000032, A084057, A087131, A269991.
%K A269992 nonn,cons,easy
%O A269992 1,2
%A A269992 _Clark Kimberling_, Mar 12 2016