A251031 Number of (n+1)X(2+1) 0..3 arrays with nondecreasing min(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

711, 6089, 45150, 304421, 1946207, 12029009, 72779934, 434254685, 2567561554, 15090103381, 88339885078, 515834692826, 3007119808000, 17512206122415, 101918872298431, 592932297654670, 3448775579665480, 20057632093436960

Offset

1,1

Comments

Column 2 of A251037

Links

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

Formula

Empirical: a(n) = 38*a(n-1) -640*a(n-2) +6224*a(n-3) -37777*a(n-4) +140106*a(n-5) -246243*a(n-6) -311318*a(n-7) +2866723*a(n-8) -6221140*a(n-9) +1267287*a(n-10) +20418382*a(n-11) -36000935*a(n-12) -3163420*a(n-13) +76544079*a(n-14) -62345650*a(n-15) -62658186*a(n-16) +109336358*a(n-17) +10886761*a(n-18) -92320878*a(n-19) +17077256*a(n-20) +47426642*a(n-21) -13020476*a(n-22) -16187272*a(n-23) +3593112*a(n-24) +3641608*a(n-25) -208432*a(n-26) -421728*a(n-27) -60480*a(n-28)

Example

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

Crossrefs

Sequence in context: A265197 A269060 A265142 * A256509 A259674 A321493

Adjacent sequences: A251028 A251029 A251030 * A251032 A251033 A251034

Keyword

nonn

Author

R. H. Hardin, Nov 29 2014

Status

approved