A235767 Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise

46, 178, 628, 1948, 5643, 15185, 39029, 95779, 227803, 525427, 1185737, 2620063, 5700715, 12222279, 25917801, 54393195, 113263283, 234136955, 481329353, 984473879, 2005754987, 4072140479, 8245166361, 16654521715, 33579036115

Offset

1,1

Comments

Column 2 of A235772

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +6*a(n-2) -42*a(n-3) +5*a(n-4) +178*a(n-5) -130*a(n-6) -380*a(n-7) +440*a(n-8) +400*a(n-9) -688*a(n-10) -128*a(n-11) +528*a(n-12) -96*a(n-13) -160*a(n-14) +64*a(n-15)

Example

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

Crossrefs

Sequence in context: A350556 A251467 A251460 * A192850 A211334 A160334

Adjacent sequences: A235764 A235765 A235766 * A235768 A235769 A235770

Keyword

nonn

Author

R. H. Hardin, Jan 15 2014

Status

approved