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 A174251 #6 Jun 01 2022 11:34:31 %S A174251 1,1,7,259,9525,270827,6633399,158753814,3825111851,96608374284, %T A174251 2446223788303 %N A174251 Number of tilings of a 7 X n rectangle with n heptominoes of any shape. %H A174251 R. S. Harris, <a href="http://www.bumblebeagle.org/polyominoes/tilingcounting/counting_9x9_tilings.pdf">Counting Nonomino Tilings and Other Things of that Ilk</a>, G4G9 Gift Exchange book, 2010. %H A174251 R. S. Harris, <a href="http://www.bumblebeagle.org/polyominoes/tilingcounting">Counting Polyomino Tilings</a> %Y A174251 Cf. A134438, A174248, A174249, A174250, A174252, A174253. %K A174251 nonn,more %O A174251 0,3 %A A174251 Bob Harris (me13013(AT)gmail.com), Mar 13 2010