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 A233429 #11 Feb 07 2017 17:28:17 %S A233429 1,501,890989,1666772813,3125064284901,5859766228545967, %T A233429 10987595369808657169,20602741350971679371521, %U A233429 38632014757792375332001835,72438542874037975287077565935,135828859204452470219311220073385,254691470323770059993623356733063003 %N A233429 Number of tilings of a 4 X 5n rectangle with 4n pentominoes of any shape. %H A233429 Alois P. Heinz, <a href="/A233429/b233429.txt">Table of n, a(n) for n = 0..100</a> %H A233429 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentomino">Pentomino</a> %F A233429 a(n) ~ c * d^n, where d = 1875.09099182186211660253860201132854810972459605757360689785461004..., c = 0.25279505771792803447854701369537504374767224177480509542292622525... . - _Vaclav Kotesovec_, Mar 05 2016 %Y A233429 Quintisection of column k=4 of A233427. %K A233429 nonn %O A233429 0,2 %A A233429 _Alois P. Heinz_, Dec 09 2013