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A200770 Number of nX1 0..2 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

%I A200770 #9 Jul 22 2025 15:55:17
%S A200770 3,3,2,7,9,6,22,30,20,75,105,70,266,378,252,966,1386,924,3564,5148,
%T A200770 3432,13299,19305,12870,50050,72930,48620,189618,277134,184756,722228,
%U A200770 1058148,705432,2762942,4056234,2704156,10608612,15600900,10400600,40859500
%N A200770 Number of nX1 0..2 arrays with every row and column running average nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.
%C A200770 Column 1 of A200777
%H A200770 R. H. Hardin, <a href="/A200770/b200770.txt">Table of n, a(n) for n = 1..210</a>
%F A200770 Conjecture: (n+2)*(2270*n-4893)*a(n) +3*(1090*n^2-4919*n+1654)*a(n-1) +4686*a(n-2) +2*(-5540*n^2+7016*n+17127)*a(n-3) -6*(1090*n-2739)*(2*n-7)*a(n-4)=0. - R. J. Mathar, Nov 23 2011
%e A200770 All solutions for n=4
%e A200770 ..0....0....0....0....0....0....0
%e A200770 ..0....2....0....1....1....1....2
%e A200770 ..1....1....2....2....2....1....1
%e A200770 ..2....2....1....2....1....2....1
%Y A200770 Includes A003409((n+1)/3) and A000984(n/3)
%K A200770 nonn
%O A200770 1,1
%A A200770 _R. H. Hardin_ Nov 22 2011