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 A023564 #3 Mar 30 2012 18:55:52 %S A023564 0,2,5,7,12,18,22,28,35,43,51,58,67,77,87,97,108,119,129,141,155,167, %T A023564 181,194,206,221,235,251,266,282,299,314,329,345,363,382,399,418,438, %U A023564 454,473,491,509,531,551,571,594,614,635,655,676,699,719 %N A023564 Convolution of A023531 and A001950. %K A023564 nonn %O A023564 1,2 %A A023564 _Clark Kimberling_