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 A063651 #18 Oct 30 2022 18:19:59 %S A063651 1,1,21,85,747,4375,31387,202841,1382259,9167119,61643709,411595537, %T A063651 2758179839,18448963469,123518353059,826573277157,5532716266089, %U A063651 37028886137273,247839719105625,1658772577825883,11102227136885119 %N A063651 Number of ways to tile a 7 X n rectangle with 1 X 1 and 2 X 2 tiles. %H A063651 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (3,30,-17,-138,85,116,-42,-32). %F A063651 a(n) = 3a(n-1) + 30a(n-2) - 17a(n-3) - 138a(n-4) + 85a(n-5) + 116a(n-6) - 42a(n-7) - 32a(n-8). - Keith Schneider (kschneid(AT)bulldog.unca.edu), Apr 02 2006 %F A063651 G.f.: ( 1 -2*x -12*x^2 +9*x^3 +17*x^4 -6*x^5 -6*x^6 ) / ( 1 -3*x -30*x^2 +17*x^3 +138*x^4 -85*x^5 -116*x^6 +42*x^7 +32*x^8 ). - _Colin Barker_, Nov 29 2012 %Y A063651 Cf. A001045, A054854, A054855, A063650-A063654. %Y A063651 Column k=7 of A245013. %K A063651 nonn,easy %O A063651 0,3 %A A063651 _Reiner Martin_, Jul 23 2001