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 A098432 #8 Aug 23 2020 06:33:10 %S A098432 1,8,7,128,304,177,3072,13952,21080,10199,98304,724992,2016000, %T A098432 2441056,1051745,3932160,42762240,187643904,407505664,428605352, %U A098432 169913511,188743680,2839019520,17974591488,60428242944,111985428352 %N A098432 Coefficients of polynomials S(n,x) related to Springer numbers. %H A098432 A. Randrianarivony and J. Zeng, <a href="http://math.univ-lyon1.fr/homes-www/zeng/public_html/paper/publication.html">Une famille des polynomes qui interpole plusieurs suites...</a>, Adv. Appl. Math. 17 (1996), 1-26. %F A098432 Recurrence: S(0, x)=1, S(n, x)=(2x+2)(2x+4)S(n-1, x+2)-(2x+1)^2S(n-1, x). %F A098432 G.f.: Sum[n>=0, S(n, x)t^n] = 1/(1+t-4*2(x+1)t/(1-4*2(x+2)t/(1+t-4*4(x+3)t/(1-4+4(x+4)t/...)))). %e A098432 S(0,x) = 1, %e A098432 S(1,x) = 8*x + 7, %e A098432 S(2,x) = 128*x^2 + 304*x + 177, %e A098432 S(3,x) = 3072*x^3 + 13952*x^2 + 21080*x + 10199. %o A098432 (PARI) S(n,x)=if(n<1,1,(2*x+2)*(2*x+4)*S(n-1,x+2)-(2*x+1)^2*S(n-1,x)) %Y A098432 Cf. A001586. S(n, 1/2) = A000464(n+1), S(n, -1/2) = A000281(n). %Y A098432 Leading coefficients are A051189. Constant terms are in A098433. %Y A098432 Cf. A001586. S(n, 1/2) = A000464(n), S(n, -1/2) = A000281(n). %K A098432 tabl,nonn %O A098432 0,2 %A A098432 _Ralf Stephan_, Sep 07 2004