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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
OFFSET
1,1
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 28 2014
STATUS
approved