A251022 Number of (n+1)X(2+1) 0..3 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements

526, 2546, 8207, 23404, 60044, 144737, 334167, 755336, 1690491, 3781186, 8485355, 19144607, 43420578, 98930808, 226191116, 518462850, 1190424308, 2736380757, 6294485365, 14485586642, 33344734931, 76769227278, 176761167633

Offset

1,1

Comments

Column 2 of A251028

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -25*a(n-2) +35*a(n-3) -7*a(n-4) -49*a(n-5) +77*a(n-6) -55*a(n-7) +20*a(n-8) -3*a(n-9) for n>13

Example

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

Crossrefs

Sequence in context: A168308 A294984 A020379 * A251108 A204472 A264804

Adjacent sequences: A251019 A251020 A251021 * A251023 A251024 A251025

Keyword

nonn

Author

R. H. Hardin, Nov 29 2014

Status

approved