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 A206466 #10 Jun 16 2018 16:02:47 %S A206466 121,1411,11025,106891,958441,8963667,82609921,767387611,7109019225, %T A206466 65954564131,611588125681,5672733227307,52611971134921, %U A206466 487976540781811,4525907460768225,41977494854894971,389337236836785721 %N A206466 Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having zero permanent. %C A206466 Column 2 of A206472. %H A206466 R. H. Hardin, <a href="/A206466/b206466.txt">Table of n, a(n) for n = 1..210</a> %F A206466 Empirical: a(n) = 11*a(n-1) - 176*a(n-3) + 256*a(n-4). %F A206466 Empirical g.f.: x*(121 + 80*x - 4496*x^2 + 6912*x^3) / ((1 - 4*x)*(1 + 4*x)*(1 - 11*x + 16*x^2)). - _Colin Barker_, Jun 16 2018 %e A206466 Some solutions for n=4: %e A206466 2 2 1 2 1 0 2 2 1 0 0 0 0 0 1 0 0 0 2 0 1 %e A206466 0 0 0 0 0 0 0 0 0 1 2 0 1 0 1 0 1 2 2 0 1 %e A206466 0 0 2 1 1 0 2 1 1 0 0 0 2 0 2 0 0 0 1 0 1 %e A206466 2 0 1 0 0 0 0 0 0 1 1 2 0 0 1 2 1 2 0 0 1 %e A206466 0 0 2 0 0 2 1 1 0 0 0 0 1 0 0 0 0 0 2 0 1 %Y A206466 Cf. A206472. %K A206466 nonn %O A206466 1,1 %A A206466 _R. H. Hardin_, Feb 08 2012