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A233109 Number of nX4 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.

%I A233109 #6 Jul 23 2025 07:53:14
%S A233109 23,6046,2154065,794723482,294285758398,109015274761891,
%T A233109 40385221182281560,14960955484170769147,5542380989283805407733,
%U A233109 2053210330075493118514936,760624844506193044187974495
%N A233109 Number of nX4 0..5 arrays with no element x(i,j) adjacent to value 5-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order.
%C A233109 Column 4 of A233113
%H A233109 R. H. Hardin, <a href="/A233109/b233109.txt">Table of n, a(n) for n = 1..210</a>
%F A233109 Empirical: a(n) = 445*a(n-1) -29415*a(n-2) +684239*a(n-3) -6544703*a(n-4) +26009211*a(n-5) -37153497*a(n-6) +17033721*a(n-7)
%e A233109 Some solutions for n=2
%e A233109 ..0..1..5..4....0..1..2..4....0..1..2..5....0..1..2..2....0..1..2..5
%e A233109 ..2..5..4..2....1..5..2..5....4..3..0..3....1..0..1..2....3..5..4..5
%K A233109 nonn
%O A233109 1,1
%A A233109 _R. H. Hardin_, Dec 04 2013