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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. 1
344, 2064, 12408, 76188, 455160, 2721900, 16378560, 100568160, 600811200, 3592908000, 21619699200, 132749971200, 793070784000, 4742638560000, 28538002944000, 175229961984000, 1046853434880000, 6260282899200000 (list; graph; refs; listen; history; text; internal format)
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

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Last modified January 29 02:35 EST 2022. Contains 350672 sequences. (Running on oeis4.)