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 A215643 #23 Feb 07 2021 07:04:12 %S A215643 1,1,2,15,104,890,8814,100660,1288048,18337680,286674960,4882660464, %T A215643 89880715704,1777384045944,37552294300416,843830334815640, %U A215643 20086549955304384,504750167170162944,13348550475903813120,370499740676381737728,10766442934111876381440 %N A215643 n-th derivative of x^((x^(x^x))^x) at x=1. %C A215643 Also n-th derivative of x^((x^x)^(x^x)) = x^(x^(x^x*x)) at x=1. %H A215643 Alois P. Heinz, <a href="/A215643/b215643.txt">Table of n, a(n) for n = 0..400</a> %F A215643 E.g.f.: (x+1)^(((x+1)^((x+1)^(x+1)))^(x+1)). %p A215643 a:= n-> n!*coeff(series(subs(x=x+1, x^((x^(x^x))^x) ), x, n+1), x, n): %p A215643 seq(a(n), n=0..30); %t A215643 m = 20; %t A215643 CoefficientList[(x+1)^(((x+1)^((x+1)^(x+1)))^(x+1)) + O[x]^(m+1), x]* Range[0, m]! (* _Jean-François Alcover_, Feb 07 2021 *) %Y A215643 Column k=15 of A215703. %Y A215643 Cf. A005727, A179230, A179405, A215522, A215524. %K A215643 nonn %O A215643 0,3 %A A215643 _Alois P. Heinz_, Aug 18 2012