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A230671 Number of nX4 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).

%I A230671 #6 Jun 02 2025 08:44:57
%S A230671 9,513,18915,730503,28368687,1100265795,42681522741,1655698076319,
%T A230671 64227455495727,2491499259313149,96649752790452639,
%U A230671 3749218360204902945,145438947787185663525,5641839307719342400131,218857130513207098732227
%N A230671 Number of nX4 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).
%C A230671 Column 4 of A230675
%H A230671 R. H. Hardin, <a href="/A230671/b230671.txt">Table of n, a(n) for n = 1..210</a>
%F A230671 Empirical: a(n) = 37*a(n-1) +85*a(n-2) -427*a(n-3) -7212*a(n-4) +18333*a(n-5) -11460*a(n-6) -144161*a(n-7) +427156*a(n-8) -283771*a(n-9) -737876*a(n-10) +2778226*a(n-11) -6632316*a(n-12) +11370217*a(n-13) -12647443*a(n-14) +15533606*a(n-15) -15672799*a(n-16) +13230743*a(n-17) -12231559*a(n-18) +8238905*a(n-19) -5597330*a(n-20) +3725581*a(n-21) -1775475*a(n-22) +1133310*a(n-23) -535263*a(n-24) +157955*a(n-25) -84089*a(n-26) +33686*a(n-27) -7250*a(n-28) +372*a(n-29) +636*a(n-30) -360*a(n-31) +72*a(n-32)
%e A230671 Some solutions for n=3
%e A230671 ..0..2..2..2....2..0..1..1....2..0..2..2....1..0..2..2....0..1..1..1
%e A230671 ..0..0..0..2....2..0..2..1....2..2..0..2....1..1..0..0....0..2..0..2
%e A230671 ..2..2..0..2....2..0..2..0....1..1..1..2....1..1..2..0....0..2..2..0
%K A230671 nonn
%O A230671 1,1
%A A230671 _R. H. Hardin_, Oct 27 2013