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 A247196 #14 Feb 07 2017 10:22:46 %S A247196 1,1,3,7,17,78,199,638,1865,5332,17250,50877,156787,475348,1423432, %T A247196 4367178,13182353,40122074,121916294,369052634,1122475534,3403574961, %U A247196 10335095973,31385295907,95218937465,289154182737,877572289140,2663965244527,8087517963748 %N A247196 Number of tilings of a 5 X n rectangle using n pentominoes of shapes T, I, P. %H A247196 Alois P. Heinz, <a href="/A247196/b247196.txt">Table of n, a(n) for n = 0..1000</a> %H A247196 Wikipedia, <a href="https://en.wikipedia.org/wiki/Pentomino">Pentomino</a> %e A247196 a(3) = 7: %e A247196 ._____. ._____. ._____. ._____. ._____. ._____. ._____. %e A247196 |_. | | | | | | | | | | | | | | | | | | ._| %e A247196 | |___| | | ._| | | | | | |_. | |_. | | | ._| | |___| | %e A247196 | .___| | |_| | | | | | | | |_| | |_| | |_| | | |___. | %e A247196 |_| | | | | | | | | | | | | | | | | | | |_| %e A247196 |_____| |_|___| |_|_|_| |_|___| |___|_| |___|_| |_____| . %Y A247196 Cf. A174249, A233427, A246764, A247103. %K A247196 nonn %O A247196 0,3 %A A247196 _Alois P. Heinz_, Nov 24 2014