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 A380387 #10 Feb 15 2025 14:16:00
%S A380387 1,6,2,3,2,4,6,3,7,6,2,3,9,2,9,7,8,5,9,5,9,7,9,7,3,3,5,8,3,6,2,2,4,0,
%T A380387 9,1,7,0,0,0,4,8,3,7,9,2,2,8,8,1,5,9,4,9,1,9,3,4,4,2,9,3,8,9,7,0,7,8,
%U A380387 5,3,2,4,7,6,9,0,1,9,5,2,4,7,9,7,2,0
%N A380387 Decimal expansion of Sum_{n>=1} lambda(n)/2^n where lambda is the Liouville function (A008836).
%C A380387 Close in value to log(zeta(Pi)) = 0.162324388... (A300892).
%F A380387 Equals 2*A343784 - 1. - _Hugo Pfoertner_, Jan 25 2025
%e A380387 0.16232463762392978595979733583622409170004837922881594919344293897...
%t A380387 RealDigits[Sum[N[LiouvilleLambda[n]/ 2^n, 128], {n, 300}], 10, 86][[1]]
%o A380387 (PARI) suminf(n=1, (-1)^bigomega(n)/2^n) \\ _Michel Marcus_, Jan 23 2025
%Y A380387 Cf. A008836, A238270, A300892, A343784.
%K A380387 nonn,cons
%O A380387 0,2
%A A380387 _Friedjof Tellkamp_, Jan 23 2025