A235737 Number of (n+1)X(1+1) 0..2 arrays with the sum of each 2X2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise

81, 576, 3992, 26088, 167892, 1060410, 6648825, 41411637, 257111073, 1592383950, 9849348220, 60864784416, 375923971008, 2321047520028, 14327865017369, 88434810763449, 545798500182681, 3368378623889316, 20787263257726248

Offset

1,1

Comments

Column 1 of A235742

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -144*a(n-3) +122*a(n-4) +726*a(n-5) -372*a(n-6) -1500*a(n-7) +239*a(n-8) +1353*a(n-9) +156*a(n-10) -444*a(n-11) -144*a(n-12)

Example

Some solutions for n=5
..0..2....1..2....2..0....1..2....0..2....0..2....0..0....0..1....1..0....1..1
..0..0....0..0....0..0....1..1....1..0....1..1....2..0....2..0....2..0....2..1
..0..2....2..0....0..2....2..2....2..0....0..2....1..0....1..2....0..0....2..1
..0..2....0..1....0..2....2..0....1..1....1..0....2..2....2..0....2..0....1..2
..0..0....0..2....1..2....0..0....1..1....2..1....0..0....1..1....0..2....2..0
..1..2....1..0....0..2....1..2....1..0....2..0....2..2....1..1....1..1....2..0

Crossrefs

Sequence in context: A237028 A235742 A236082 * A236490 A235437 A235432

Adjacent sequences: A235734 A235735 A235736 * A235738 A235739 A235740

Keyword

nonn

Author

R. H. Hardin, Jan 15 2014

Status

approved