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

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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences: A200767 A200768 A200769 * A200771 A200772 A200773

Keyword

nonn

Author

R. H. Hardin Nov 22 2011

Status

approved