A250685 Number of (n+1)X(2+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

543, 2920, 15246, 76320, 362241, 1647460, 7249825, 31113316, 131014715, 543845812, 2233368847, 9098214240, 36844025643, 148553970588, 597082293823, 2394504059784, 9587995012203, 38352450171812, 153311305422383

Offset

1,1

Comments

Column 2 of A250691

Links

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

Formula

Empirical: a(n) = 27*a(n-1) -331*a(n-2) +2439*a(n-3) -12049*a(n-4) +42129*a(n-5) -107225*a(n-6) +201069*a(n-7) -277706*a(n-8) +278928*a(n-9) -197984*a(n-10) +94032*a(n-11) -26784*a(n-12) +3456*a(n-13) for n>17

Example

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

Crossrefs

Sequence in context: A268146 A074888 A250854 * A051305 A204732 A204725

Adjacent sequences: A250682 A250683 A250684 * A250686 A250687 A250688

Keyword

nonn

Author

R. H. Hardin, Nov 26 2014

Status

approved