A253395 Number of (n+1) X (6+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.

476, 320, 419, 632, 932, 1318, 1855, 2528, 3408, 4498, 5864, 7521, 9542, 11949, 14824, 18197, 22158, 26745, 32056, 38137, 45094, 52981, 61912, 71949, 83214, 95777, 109768, 125265, 142406, 161277, 182024, 204741, 229582, 256649, 286104, 318057

Offset: 1

Author

R. H. Hardin, Dec 31 2014

Keywords

• nonn

Examples

			Some solutions for n=4:
..0..1..0..1..0..1..1....1..1..1..0..0..0..1....1..1..1..1..1..1..1
..0..1..0..1..0..1..0....1..1..1..1..1..1..1....1..1..1..0..0..0..0
..0..1..0..1..0..1..0....1..1..0..0..0..0..0....1..1..1..1..1..1..1
..0..1..0..1..0..1..0....1..1..1..1..1..1..1....1..0..0..0..0..0..0
..0..1..0..1..0..1..0....0..0..0..0..0..0..0....0..0..1..1..1..1..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Column 6 of A253397.

Formula

Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + 5*a(n-4) - 4*a(n-5) + a(n-6) for n>16.

Empirical for n mod 2 = 0: a(n) = (1/6)*n^4 + (185/6)*n^2 - 61*n + 357 for n>10.

Empirical for n mod 2 = 1: a(n) = (1/6)*n^4 + (185/6)*n^2 - 61*n + 364 for n>10.

Empirical g.f.: x*(476 - 1584*x + 1519*x^2 + 556*x^3 - 1881*x^4 + 1054*x^5 - 48*x^6 - 106*x^7 + 20*x^8 + 12*x^9 - 23*x^10 + 17*x^11 - 5*x^12 + 2*x^14 - x^15) / ((1 - x)^5*(1 + x)). - Colin Barker, Dec 12 2018