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A258558 Number of (5+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically. 1
480, 1329, 2384, 3754, 5070, 6662, 8612, 10720, 12831, 15045, 17532, 20200, 22894, 25714, 28830, 32150, 35519, 39037, 42874, 46938, 51074, 55382, 60032, 64932, 69927, 75117, 80672, 86500, 92446, 98610, 105162, 112010, 118999, 126229, 133870, 141830 (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) - 3*a(n-2) + a(n-3) + a(n-4) - 3*a(n-5) + 3*a(n-6) - a(n-7) for n>12.

Empirical g.f.: x*(480 - 111*x - 163*x^2 + 109*x^3 - 849*x^4 + 441*x^5 + 245*x^6 - 309*x^7 + 214*x^8 - 230*x^9 + 88*x^10 + 108*x^11) / ((1 - x)^4*(1 + x)*(1 + x^2)). - Colin Barker, Dec 22 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Row 5 of A258554.

Sequence in context: A108876 A293187 A206200 * A083728 A199808 A253401

Adjacent sequences:  A258555 A258556 A258557 * A258559 A258560 A258561

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 03 2015

STATUS

approved

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Last modified July 30 17:21 EDT 2021. Contains 346359 sequences. (Running on oeis4.)