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 A214136 #8 Jul 22 2025 23:09:45 %S A214136 4,257,28278,3221873,367793014,41989913081,4793901053846, %T A214136 547309896088193,62485254609615222,7133814088846153097, %U A214136 814453006155085388566,92984438755466611752209,10615843744610501570047094 %N A214136 Number of 0..4 colorings on an nX4 array circular in the 4 direction with new values 0..4 introduced in row major order. %C A214136 Column 3 of A214141 %H A214136 R. H. Hardin, <a href="/A214136/b214136.txt">Table of n, a(n) for n = 1..210</a> %F A214136 Empirical: a(n) = 129*a(n-1) -1759*a(n-2) +7575*a(n-3) -9064*a(n-4) +3120*a(n-5). %F A214136 Empirical: G.f. -x*(4-259*x+2161*x^2-4226*x^3+1880*x^4) / ( (x-1) *(780*x^2-121*x+1) *(4*x^2-7*x+1) ). - _R. J. Mathar_, Jul 05 2012 %e A214136 Some solutions for n=4 %e A214136 ..0..1..0..1....0..1..2..3....0..1..0..1....0..1..0..1....0..1..0..2 %e A214136 ..2..3..4..3....4..2..4..2....2..0..3..0....1..2..1..2....3..4..1..4 %e A214136 ..1..2..3..4....3..1..0..1....4..3..1..2....0..1..3..4....0..3..4..2 %e A214136 ..2..3..2..0....1..2..1..0....0..4..0..4....3..4..1..0....4..0..1..3 %K A214136 nonn %O A214136 1,1 %A A214136 _R. H. Hardin_ Jul 05 2012