A237378 Number of (n+1) X (2+1) 0..2 arrays with the maximum plus the minimum minus the upper median minus the lower median of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one.

344, 2064, 12408, 76188, 455160, 2721900, 16378560, 100568160, 600811200, 3592908000, 21619699200, 132749971200, 793070784000, 4742638560000, 28538002944000, 175229961984000, 1046853434880000, 6260282899200000

Offset

1,1

Links

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

Formula

Empirical: a(n) = 1320*a(n-4) for n>6.

Empirical g.f.: 4*x*(86 + 516*x + 3102*x^2 + 19047*x^3 + 270*x^4 - 645*x^5) / (1 - 1320*x^4). - Colin Barker, Oct 22 2018

Example

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

Crossrefs

Column 2 of A237384.

Sequence in context: A044878 A085336 A236090 * A237243 A183680 A183674

Adjacent sequences: A237375 A237376 A237377 * A237379 A237380 A237381

Keyword

nonn

Author

R. H. Hardin, Feb 07 2014

Status

approved