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A253156 Number of (n+1) X (5+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically. 1
181, 192, 201, 236, 308, 452, 740, 1316, 2468, 4772, 9380, 18596, 37028, 73892, 147620, 295076, 589988, 1179812, 2359460, 4718756, 9437348, 18874532, 37748900, 75497636, 150995108, 301990052, 603979940, 1207959716, 2415919268, 4831838372 (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) = 3*a(n-1) -2*a(n-2) for n>5.

Empirical: a(n) = 9*2^(n-1) + 164 for n>3.

Empirical g.f.: x*(181 - 351*x - 13*x^2 + 17*x^3 + 2*x^4) / ((1 - x)*(1 - 2*x)). - Colin Barker, Dec 09 2018

EXAMPLE

Some solutions for n=6:

..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

..0..0..0..0..0..0....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

..1..1..1..1..1..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

..1..1..1..1..1..1....0..0..0..0..0..0....1..0..1..0..0..1....1..0..0..0..0..0

..0..0..0..0..0..0....0..0..0..0..0..0....1..0..1..0..0..1....1..0..0..0..0..0

..0..0..0..0..0..1....1..1..1..1..1..1....1..0..1..0..0..1....1..0..0..0..0..0

CROSSREFS

Column 5 of A253159.

Sequence in context: A253439 A175789 A157747 * A139649 A159263 A159548

Adjacent sequences:  A253153 A253154 A253155 * A253157 A253158 A253159

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 28 2014

STATUS

approved

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Last modified January 22 21:47 EST 2022. Contains 350504 sequences. (Running on oeis4.)