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 A371325 #5 Mar 19 2024 10:28:56
%S A371325 4,2,3,6,1,0,5,0,8,3,0,6,3,8,1,2,6,4,0,7,8,8,3,9,3,5,9,7,0,2,1,7,4,1,
%T A371325 5,5,3,3,6,7,2,6,6,9,9,2,6,8,7,2,6,0,6,1,7,4,0,4,6,6,9,1,7,4,7,4,7,6,
%U A371325 6,9,2,0,9,3,4,9,4,7,9,7,1,2,8,4,9,2,3,5,7,9,1,3,7,3,4,6,1,1,5,2,3,9,9,4,5
%N A371325 Decimal expansion of Sum_{k>=1} (-1)^(k+1)/(2^k * Lucas(k!)).
%C A371325 The transcendence of this constant was proved by Nyblom (2004).
%H A371325 M. A. Nyblom, <a href="https://doi.org/10.1016/j.jnt.2003.09.005">An extension of a result of Sierpiński</a>, Journal of Number Theory, Vol. 105, No. 1 (2004), pp. 49-59.
%H A371325 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%e A371325 0.42361050830638126407883935970217415533672669926872...
%t A371325 RealDigits[-Sum[(-1/2)^k/LucasL[k!], {k, 1, 10}], 10, 120][[1]]
%o A371325 (PARI) suminf(k = 1, -(-1/2)^k/(fibonacci(k!-1)+fibonacci(k!+1)))
%Y A371325 Cf. A000032, A000142, A101293, A343202, A371322, A371323, A371324.
%K A371325 nonn,cons
%O A371325 0,1
%A A371325 _Amiram Eldar_, Mar 19 2024