A254423 Number of (2+1)X(n+1) 0..2 arrays with every 2X2 subblock diagonal maximum minus antidiagonal maximum nondecreasing horizontally, vertically and ne-to-sw antidiagonally

470, 3279, 25589, 229652, 2128339, 19879926, 186426904, 1752614398, 16501742450, 155519360130, 1466527601250, 13834051837650, 130527440933858, 1231716994177714, 11623968878478050, 109703076280582962

Offset

1,1

Comments

Row 2 of A254422

Links

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

Formula

Empirical: a(n) = 21*a(n-1) -139*a(n-2) +191*a(n-3) +1344*a(n-4) -4896*a(n-5) +1972*a(n-6) +10548*a(n-7) -8240*a(n-8) -8576*a(n-9) +4704*a(n-10) +3072*a(n-11) for n>18

Example

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

Crossrefs

Sequence in context: A251779 A251772 A253518 * A254416 A251771 A251152

Adjacent sequences: A254420 A254421 A254422 * A254424 A254425 A254426

Keyword

nonn

Author

R. H. Hardin, Jan 30 2015

Status

approved