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 A099876 #14 Feb 04 2025 11:21:23 %S A099876 1,8,2,7,0,1,4,7,1,7,6,0,8,5,9,2,2,2,6,3,7,3,8,4,3,1,9,2,8,5,2,8,9,2, %T A099876 4,7,3,7,4,7,9,3,6,2,9,6,0,8,2,5,4,8,5,4,4,2,6,1,6,2,4,6,2,9,5,6,2,1, %U A099876 0,0,1,5,2,3,8,7,0,9,6,7,2,7,8,3,1,0,7,2,4,4,1,6,6,1,4,3,0,5,5,5,0 %N A099876 Decimal expansion of a nested radical: sqrt(1! + sqrt(2! + sqrt(3! + ... %H A099876 Chai Wah Wu, <a href="/A099876/b099876.txt">Table of n, a(n) for n = 1..10000</a> %H A099876 Popular Computing (Calabasas, CA), <a href="/A257352/a257352.pdf">The CSR Function</a>, Vol. 4 (No. 34, Jan 1976), pages PC34-10 to PC34-11. Annotated and scanned copy. %e A099876 1.82701471760859222637384319285... %t A099876 RealDigits[Fold[Sqrt[#1 + #2] &, 0, Reverse[Range[100]!]], 10, 111][[1]] %o A099876 (PARI) t=0; forstep(n=300,1,-1,t=sqrt(t+n!)); t \\ gives more than enough correct digits for the number given here. %Y A099876 Cf. A072449, A099874. %K A099876 cons,easy,nonn %O A099876 1,2 %A A099876 Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 02 2004