A254254 Number of (n+2) X (2+2) 0..1 arrays with every 3 X 3 subblock sum of the two maximums of the diagonal and antidiagonal minus the sum of the minimums of the central row and column nondecreasing horizontally, vertically and ne-to-sw antidiagonally.

2812, 14681, 59531, 223357, 888391, 3647288, 15380009, 65954108, 284203166, 1230877185, 5342480244, 23208777649, 100906958889, 438856975356, 1908960099543, 8304782737694, 36130959962354, 157196994230935

Offset

1,1

Comments

Column 2 of A254260.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +9*a(n-2) -12*a(n-3) -105*a(n-4) -35*a(n-5) +376*a(n-6) +453*a(n-7) -295*a(n-8) -1041*a(n-9) -767*a(n-10) +468*a(n-11) +1203*a(n-12) +829*a(n-13) +48*a(n-14) -921*a(n-15) -766*a(n-16) +251*a(n-17) +334*a(n-18) +12*a(n-19) -36*a(n-20) -8*a(n-21) for n > 25.

Example

Some solutions for n=3
..0..0..0..1....1..1..1..0....0..1..1..0....1..0..1..0....0..1..0..0
..0..0..1..0....1..0..1..1....1..1..1..1....0..0..1..1....1..1..1..1
..0..1..1..0....1..0..0..0....1..1..1..1....1..0..0..0....0..1..0..1
..1..0..0..0....1..1..0..1....0..1..0..1....0..0..1..1....1..0..1..1
..1..1..1..1....0..1..1..1....1..1..0..0....1..1..0..0....1..1..1..0

Crossrefs

Cf. A254260.

Sequence in context: A031551 A031731 A252048 * A254261 A258524 A258531

Adjacent sequences: A254251 A254252 A254253 * A254255 A254256 A254257

Keyword

nonn

Author

R. H. Hardin, Jan 27 2015

Status

approved