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 A136587 #3 Mar 30 2012 17:34:23 %S A136587 2,-2,1,1,6,0,-8,0,1,-48,-5,87,1,-20,0,1,392,0,-984,0,346,0,-35,0,1, %T A136587 -3840,33,12645,-14,-6090,1,938,0,-54,0,1,46032,0,-187338,0,114745,0, %U A136587 -23813,0,2070,0,-77,0,1,-645120,-279,3133935,185,-2336040,-27,611415,1,-71280,0,3993,0,-104,0,1,10322304,0,-58438830,0 %N A136587 Triangle of coefficients of even modified recursive orthogonal Hermite polynomials given in Hochstadt's book:P(x, n) = x*P(x, n - 1) - n*P(x, n - 2) ;A137286; P2(x,n)=P(x,n)+P(x,2*n): second type. %C A136587 Row sums are: %C A136587 {2, 0, -1, 16, -280, 3620, -48380, 696680, -10740280, 175631200, -3000871600} %C A136587 The double function Integration is not orthogonal: %C A136587 Table[Integrate[Exp[ -x^2/2]*P2[x, n]*P2[x, m], {x, -Infinity, Infinity}], {n, 0, 10}, {m, 0, 10}]; %C A136587 Both types have the polynomial: %C A136587 p[x]=6 - 8 x^2 + x^4 %C A136587 Original Hermite has: %C A136587 p[x]=8 - 9 x^2 + x^4 %C A136587 Integration of these as: %C A136587 f[y_] = Integrate[Exp[ -x^2/4]*p[x], {x, Infinity, y}] %C A136587 g[z_] = Integrate[Exp[ -y^2/4]*f[y], {y, Infinity, z}] %C A136587 gives three level or four level curves with negative limit of 2*Pi. %F A136587 H2(x,n)=A137286(x,n)+A137286(x,2*n) %e A136587 {2}, %e A136587 {-2, 1, 1}, %e A136587 {6, 0, -8, 0, 1}, %e A136587 {-48, -5, 87,1, -20, 0, 1}, %e A136587 {392, 0, -984, 0, 346, 0, -35, 0, 1}, %e A136587 {-3840, 33, 12645, -14, -6090, 1, 938, 0, -54, 0, 1}, %e A136587 {46032, 0, -187338, 0,114745, 0, -23813, 0, 2070, 0, -77, 0, 1}, %e A136587 {-645120, -279, 3133935, 185, -2336040, -27, 611415, 1, -71280, 0,3993, 0, -104,0, 1}, %e A136587 {10322304, 0, -58438830, 0, 51450870, 0, -16289000, 0, 2386396, 0, -178893, 0, 7007, 0, -135, 0, 1}, %e A136587 {-185794560, 2895, 1203216525, -2640, -1223803350, %e A136587 588, 455259420, -44, -80424630, 1, 7561554, 0, -395850, 0, 11460, 0, -170, %e A136587 0, 1}, %e A136587 {3715887360, 0, -27125479980, 0, 31335461535, 0, -13408093762, 0, 2775672846, 0,-314143829, 0, 20603310, 0, -796620, 0, 17748, 0, -209, 0, 1} %t A136587 P[x, 0] = 1; P[x, 1] = x; P[x_, n_] := P[x, n] = x*P[x, n - 1] - n*P[x, n - 2]; P2[x_, n_] := P2[x, n] = P[x, n] + P[x, 2*n]; Table[ExpandAll[P2[x, n]], {n, 0, 10}]; a = Join[{0}, Table[CoefficientList[P2[x, n], x], {n, 0, 10}]]; Flatten[a] %Y A136587 Cf. A137286. %K A136587 uned,tabl,sign %O A136587 1,1 %A A136587 _Roger L. Bagula_, Mar 30 2008