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 A232958 #6 Jul 23 2025 07:46:05 %S A232958 64,1029,27441,685251,17429409,442227825,11228712351,285082486341, %T A232958 7238105184837,183771148650939,4665845904118053,118463173683294573, %U A232958 3007712801760687567,76364121654785540601,1938841730920089921489 %N A232958 Number of 4Xn 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero. %C A232958 Row 4 of A232955 %H A232958 R. H. Hardin, <a href="/A232958/b232958.txt">Table of n, a(n) for n = 1..210</a> %F A232958 Empirical: a(n) = 24*a(n-1) +76*a(n-2) -1008*a(n-3) -992*a(n-4) +8762*a(n-5) -7403*a(n-6) -2174*a(n-7) +3324*a(n-8) -416*a(n-9) -96*a(n-10) %e A232958 Some solutions for n=3 %e A232958 ..0..1..0....0..1..0....0..2..0....0..0..0....0..1..3....0..2..0....0..1..1 %e A232958 ..0..1..3....3..2..0....2..0..2....2..2..0....3..1..0....3..2..0....1..1..3 %e A232958 ..0..2..3....0..2..2....2..2..2....3..2..3....0..2..3....3..2..0....3..1..0 %e A232958 ..3..2..0....0..2..3....2..3..3....0..1..0....3..1..3....3..1..0....3..2..3 %K A232958 nonn %O A232958 1,1 %A A232958 _R. H. Hardin_, Dec 02 2013