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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
2
3, 3, 2, 7, 9, 6, 22, 30, 20, 75, 105, 70, 266, 378, 252, 966, 1386, 924, 3564, 5148, 3432, 13299, 19305, 12870, 50050, 72930, 48620, 189618, 277134, 184756, 722228, 1058148, 705432, 2762942, 4056234, 2704156, 10608612, 15600900, 10400600, 40859500
OFFSET
1,1
COMMENTS
Column 1 of A200777
LINKS
FORMULA
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
EXAMPLE
All solutions for n=4
..0....0....0....0....0....0....0
..0....2....0....1....1....1....2
..1....1....2....2....2....1....1
..2....2....1....2....1....2....1
CROSSREFS
Includes A003409((n+1)/3) and A000984(n/3)
Sequence in context: A115055 A158468 A238278 * A265965 A192787 A268724
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 22 2011
STATUS
approved