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 A178121 #2 Mar 30 2012 18:59:27 %S A178121 1,2,1,5,6,1,16,32,12,1,64,180,109,20,1,308,1111,934,276,30,1,1727, %T A178121 7554,8095,3352,585,42,1,11008,56228,72884,39006,9580,1100,56,1,78244, %U A178121 454572,688562,451992,144706,23396,1897,72,1,611060,3962218,6845904,5317440 %N A178121 Inverse of coefficient array of orthogonal polynomials P(n,x)=(x-2n)*P(n-1,x)-(2n-3)*P(n-2,x), P(0,x)=1,P(1,x)=x-2. %C A178121 Inverse is A178120. First column is A178119. %e A178121 Triangle begins %e A178121 1, %e A178121 2, 1, %e A178121 5, 6, 1, %e A178121 16, 32, 12, 1, %e A178121 64, 180, 109, 20, 1, %e A178121 308, 1111, 934, 276, 30, 1, %e A178121 1727, 7554, 8095, 3352, 585, 42, 1, %e A178121 11008, 56228, 72884, 39006, 9580, 1100, 56, 1, %e A178121 78244, 454572, 688562, 451992, 144706, 23396, 1897, 72, 1 %e A178121 Production matrix is %e A178121 2, 1, %e A178121 1, 4, 1, %e A178121 0, 3, 6, 1, %e A178121 0, 0, 5, 8, 1, %e A178121 0, 0, 0, 7, 10, 1, %e A178121 0, 0, 0, 0, 9, 12, 1, %e A178121 0, 0, 0, 0, 0, 11, 14, 1, %e A178121 0, 0, 0, 0, 0, 0, 13, 16, 1, %e A178121 0, 0, 0, 0, 0, 0, 0, 15, 18, 1 %K A178121 nonn,tabl %O A178121 0,2 %A A178121 _Paul Barry_, May 20 2010