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A233022 Number of nX4 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, vertically, diagonally or antidiagonally, and top left element zero.

%I A233022 #8 Jul 23 2025 07:47:22
%S A233022 27,435,8835,179999,3685017,75489671,1546718177,31692006853,
%T A233022 649369155341,13305594622397,272632154901327,5586243967145293,
%U A233022 114462368539181387,2345338645585949507,48056085480976430831,984671171688465647531
%N A233022 Number of nX4 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, vertically, diagonally or antidiagonally, and top left element zero.
%C A233022 Column 4 of A233026
%H A233022 R. H. Hardin, <a href="/A233022/b233022.txt">Table of n, a(n) for n = 1..210</a>
%F A233022 Empirical: a(n) = 23*a(n-1) -39*a(n-2) -265*a(n-3) +180*a(n-4) +655*a(n-5) -156*a(n-6) -127*a(n-7) +20*a(n-8)
%F A233022 Empirical: G.f.: -x*(27-186*x-117*x^2+914*x^3+20*x^4-469*x^5+129*x^6)/(-1+23*x-39*x^2-265*x^3+180*x^4+655*x^5-156*x^6-127*x^7+20*x^8) . - _R. J. Mathar_, May 11 2022
%e A233022 Some solutions for n=4
%e A233022 ..0..2..2..2....0..0..2..2....0..2..0..0....0..0..1..3....0..0..0..2
%e A233022 ..0..2..2..2....2..2..2..2....2..0..2..0....0..0..1..1....2..2..2..0
%e A233022 ..0..0..0..2....0..2..2..0....0..2..0..2....1..0..1..1....3..2..2..0
%e A233022 ..1..0..2..2....2..2..2..0....2..0..0..0....1..0..0..1....3..2..2..0
%K A233022 nonn
%O A233022 1,1
%A A233022 _R. H. Hardin_, Dec 03 2013