A250539 Number of (n+1)X(3+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing x(i,j)-x(i-1,j) in the j direction

6627, 79366, 644779, 4169584, 23289547, 117777788, 555362165, 2489782728, 10756619019, 45218540866, 186284270079, 756106728264, 3036114535027, 12099190503944, 47969168390489, 189564322191712, 747765014131475

Offset

1,1

Comments

Column 3 of A250544

Links

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

Formula

Empirical: a(n) = 30*a(n-1) -415*a(n-2) +3514*a(n-3) -20386*a(n-4) +85924*a(n-5) -272198*a(n-6) +661180*a(n-7) -1244717*a(n-8) +1822478*a(n-9) -2068955*a(n-10) +1802474*a(n-11) -1181760*a(n-12) +563888*a(n-13) -184752*a(n-14) +37152*a(n-15) -3456*a(n-16)

Example

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

Crossrefs

Sequence in context: A237726 A345561 A345816 * A251796 A237794 A237792

Adjacent sequences: A250536 A250537 A250538 * A250540 A250541 A250542

Keyword

nonn

Author

R. H. Hardin, Nov 24 2014

Status

approved