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 A196145 #7 Jun 02 2025 04:18:23 %S A196145 17,123,178,865,2781,7486,24615,85533,266059,866323,2817802,9024682, %T A196145 29161693,94823673,306912929,992919095,3216924395,10417479713, %U A196145 33734415945,109304966265,354134153161,1147139951832,3716343382506 %N A196145 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4. %C A196145 Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 4's, every 3 is next to 3 1's, every 4 is next to 4 2's %C A196145 Column 7 of A196146 %H A196145 R. H. Hardin, <a href="/A196145/b196145.txt">Table of n, a(n) for n = 1..200</a> %e A196145 Some solutions for n=4 %e A196145 .1.0.0.1.1.0.0...1.3.1.0.0.0.1...1.0.0.1.1.0.1 %e A196145 .3.1.1.1.1.1.1...0.1.1.0.0.0.1...3.1.1.3.3.1.1 %e A196145 .1.1.1.0.0.1.1...0.1.1.1.1.1.1...1.1.1.1.1.1.0 %e A196145 .0.0.1.1.1.1.0...1.1.0.1.3.1.0...0.0.0.0.0.1.1 %K A196145 nonn %O A196145 1,1 %A A196145 _R. H. Hardin_ Sep 28 2011