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A251085 Number of (n+1) X (5+1) 0..2 arrays with no 2 X 2 subblock having the sum of its diagonal elements greater than the absolute difference of its antidiagonal elements. 1
872, 2534, 4379, 8512, 14891, 27040, 48017, 87488, 160737, 301824, 574763, 1111016, 2169343, 4270640, 8452477, 16793312, 33445781, 66718416, 133223943, 266191016, 532072547, 1063777504, 2127119369, 4253728192, 8506859561, 17013027680 (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) = 6*a(n-1) - 13*a(n-2) + 10*a(n-3) + 5*a(n-4) - 14*a(n-5) + 9*a(n-6) - 2*a(n-7) for n>8.

Empirical g.f.: x*(872 - 2698*x + 511*x^2 + 6460*x^3 - 8954*x^4 + 4098*x^5 - 27*x^6 - 320*x^7) / ((1 - x)^5*(1 + x)*(1 - 2*x)). - Colin Barker, Nov 24 2018

EXAMPLE

Some solutions for n=4:

..1..1..1..1..1..2....0..0..1..0..0..2....0..0..1..1..1..2....0..0..1..0..0..2

..0..0..0..0..0..1....0..0..1..0..0..2....0..0..0..0..0..1....0..0..1..0..0..2

..0..0..0..0..0..1....0..0..1..0..0..2....0..0..0..0..0..0....0..0..1..0..0..0

..1..0..0..0..0..1....0..0..1..0..0..2....0..0..0..0..0..0....2..0..1..0..0..0

..2..0..0..0..0..0....2..0..1..0..0..2....2..2..2..1..0..0....2..0..1..0..0..0

CROSSREFS

Column 5 of A251088.

Sequence in context: A253167 A214285 A251841 * A334011 A206312 A252211

Adjacent sequences:  A251082 A251083 A251084 * A251086 A251087 A251088

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 29 2014

STATUS

approved

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Last modified October 17 00:35 EDT 2021. Contains 348048 sequences. (Running on oeis4.)