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 A172641 #7 May 09 2020 21:21:08 %S A172641 1,3139,1376095,1849858771,2435292751411,3938448319935781, %T A172641 6887820148172502169,13039980402350138484115, %U A172641 26088526624958727703324771,54649595712626140857519780409,118790606468949916540947848175709 %N A172641 Number of n X 9 0..2 arrays with row sums 9 and column sums n. %H A172641 R. H. Hardin, <a href="/A172641/b172641.txt">Table of n, a(n) for n=1..30</a> %Y A172641 Column k=9 of A334549. %K A172641 nonn %O A172641 1,2 %A A172641 _R. H. Hardin_, Feb 06 2010