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 A214240 #6 Jul 22 2025 23:13:44 %S A214240 4,18,354,7749,231799,8178855,318511707,13046748480,547969772934, %T A214240 23296216625352,996235422019600,42723792981743991,1834737810552367569, %U A214240 78843837462576032709,3389239985131275364833,145715407979704223557482 %N A214240 Number of 0..7 colorings of a 2X(n+1) array circular in the n+1 direction with new values 0..7 introduced in row major order. %C A214240 Row 2 of A214238 %H A214240 R. H. Hardin, <a href="/A214240/b214240.txt">Table of n, a(n) for n = 1..210</a> %F A214240 Empirical: a(n) = 66*a(n-1) -867*a(n-2) -8354*a(n-3) +120414*a(n-4) +672756*a(n-5) -3902534*a(n-6) -24478884*a(n-7) +5777547*a(n-8) +189931178*a(n-9) +205081401*a(n-10) -166116762*a(n-11) -207075960*a(n-12) %e A214240 Some solutions for n=4 %e A214240 ..0..1..0..1..2....0..1..0..1..2....0..1..0..1..2....0..1..0..1..2 %e A214240 ..1..2..1..2..0....2..3..1..0..1....1..0..1..0..3....1..2..3..0..3 %K A214240 nonn %O A214240 1,1 %A A214240 _R. H. Hardin_ Jul 08 2012