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A253392 Number of (n+1) X (3+1) 0..1 arrays with every 2 X 2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically. 1
96, 143, 174, 246, 316, 419, 520, 651, 780, 939, 1096, 1283, 1468, 1683, 1896, 2139, 2380, 2651, 2920, 3219, 3516, 3843, 4168, 4523, 4876, 5259, 5640, 6051, 6460, 6899, 7336, 7803, 8268, 8763, 9256, 9779, 10300, 10851, 11400, 11979, 12556, 13163, 13768 (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) = 2*a(n-1) - 2*a(n-3) + a(n-4) for n>8.

Empirical for n mod 2 = 0: a(n) = 7*n^2 + 18*n + 59 for n>4.

Empirical for n mod 2 = 1: a(n) = 7*n^2 + 18*n + 51 for n>4.

Empirical g.f.: x*(96 - 49*x - 112*x^2 + 90*x^3 + 14*x^4 - 8*x^5 - 3*x^7) / ((1 - x)^3*(1 + x)). - Colin Barker, Dec 11 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Column 3 of A253397.

Sequence in context: A146992 A261287 A252689 * A116119 A039600 A143847

Adjacent sequences:  A253389 A253390 A253391 * A253393 A253394 A253395

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 31 2014

STATUS

approved

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Last modified May 17 14:19 EDT 2022. Contains 353746 sequences. (Running on oeis4.)