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 A299625 #9 Feb 16 2025 08:33:53 %S A299625 5,5,0,2,5,4,6,6,0,4,2,2,0,7,2,4,0,7,5,3,1,1,2,6,8,1,3,5,9,4,9,3,2,6, %T A299625 0,1,9,5,5,3,8,4,3,4,8,0,0,7,2,8,3,1,7,5,2,0,4,0,1,5,0,2,8,4,7,3,0,5, %U A299625 8,9,6,0,9,9,9,6,7,2,8,7,6,7,4,0,2,7 %N A299625 Decimal expansion of e^(2*W(2)) = 4/(W(2))^2, where W is the Lambert W function (or PowerLog); see Comments. %C A299625 The Lambert W function satisfies the functional equation e^(W(x) + W(y)) = x*y/(W(x)*W(y)) for x and y greater than -1/e, so that e^(2*W(2)) = 4/(W(2))^2. See A299613 for a guide to related constants. %H A299625 G. C. Greubel, <a href="/A299625/b299625.txt">Table of n, a(n) for n = 1..10000</a> %H A299625 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a> %e A299625 e^(2*W(2)) = 5.50254660422072407531126813594932... %t A299625 w[x_] := ProductLog[x]; x = 2; y = 2; %t A299625 N[E^(w[x] + w[y]), 130] (* A299625 *) %t A299625 RealDigits[(2/LambertW[2])^2, 10, 100][[1]] (* _G. C. Greubel_, Mar 03 2018 *) %o A299625 (PARI) (2/lambertw(2))^2 \\ _G. C. Greubel_, Mar 03 2018 %Y A299625 Cf. A299613, A299624. %K A299625 nonn,cons,easy %O A299625 1,1 %A A299625 _Clark Kimberling_, Mar 03 2018