A250700 Number of (n+1)X(1+1) 0..3 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction

100, 536, 2435, 10050, 38431, 138957, 480846, 1607723, 5230029, 16642735, 52021650, 160257157, 487831638, 1470503122, 4396997745, 13060344863, 38580263273, 113449666793, 332362403672, 970677886757, 2827666346497

Offset

1,1

Comments

Column 1 of A250707

Links

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

Formula

Empirical: a(n) = 10*a(n-1) -35*a(n-2) +35*a(n-3) +72*a(n-4) -178*a(n-5) +7*a(n-6) +259*a(n-7) -123*a(n-8) -182*a(n-9) +125*a(n-10) +68*a(n-11) -56*a(n-12) -13*a(n-13) +12*a(n-14) +a(n-15) -a(n-16)

Example

Some solutions for n=4
..0..2....0..0....0..1....0..1....0..0....0..1....2..0....0..1....1..1....1..1
..0..2....1..0....0..1....1..0....0..1....2..1....0..2....0..1....1..2....0..2
..1..2....0..1....1..3....0..1....1..0....0..3....2..2....2..2....1..2....0..2
..0..3....1..2....2..3....1..2....0..2....2..2....2..2....2..2....2..1....0..3
..1..3....1..2....3..2....3..1....2..0....3..3....1..3....1..3....1..2....3..1

Crossrefs

Sequence in context: A093004 A003588 A115695 * A250846 A172518 A357748

Adjacent sequences: A250697 A250698 A250699 * A250701 A250702 A250703

Keyword

nonn

Author

R. H. Hardin, Nov 26 2014

Status

approved