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 A196136 #7 Jun 02 2025 04:17:40 %S A196136 1,19,70,251,1350,3716,20706,63545,255501,992477,3693353,15143098, %T A196136 54682695,222402469,838015799,3238327921,12552211666,47967154876, %U A196136 187109798637,714494895572,2773237529931,10674786749417,41144890359713 %N A196136 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,2,1,3,4 for x=0,1,2,3,4. %C A196136 Every 0 is next to 0 0's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 3's, every 4 is next to 4 4's %C A196136 Column 6 of A196138 %H A196136 R. H. Hardin, <a href="/A196136/b196136.txt">Table of n, a(n) for n = 1..200</a> %e A196136 Some solutions for n=4 %e A196136 ..0..1..2..0..2..1....2..1..0..1..2..0....1..1..2..2..1..0....1..1..0..2..1..1 %e A196136 ..2..1..1..1..1..0....1..1..2..0..1..1....2..0..1..1..0..1....2..2..1..1..1..2 %e A196136 ..1..1..0..2..1..1....0..1..1..1..0..2....1..1..0..1..2..2....1..0..1..1..1..2 %e A196136 ..0..2..1..0..1..2....1..2..0..2..1..1....0..2..1..0..1..1....0..1..2..2..1..1 %K A196136 nonn %O A196136 1,2 %A A196136 _R. H. Hardin_ Sep 28 2011