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 A213834 #18 Jun 17 2017 03:06:27 %S A213834 1,10,46,140,335,686,1260,2136,3405,5170,7546,10660,14651,19670,25880, %T A213834 33456,42585,53466,66310,81340,98791,118910,141956,168200,197925, %U A213834 231426,269010,310996,357715,409510,466736 %N A213834 Antidiagonal sums of the convolution array A213833. %H A213834 Clark Kimberling, <a href="/A213834/b213834.txt">Table of n, a(n) for n = 1..1000</a> %H A213834 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1). %F A213834 a(n) = n*(n+1)*(3*n^2 - 2*n + 2)/6. %F A213834 a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5). %F A213834 G.f.: f(x)/g(x), where f(x) = x*(1 + 2*x)(1 + 3*x) and g(x) = (1-x)^5. %t A213834 (See A213833.) %Y A213834 Cf. A213833. %K A213834 nonn,easy %O A213834 1,2 %A A213834 _Clark Kimberling_, Jul 04 2012