A235444 Number of (n+1) X (3+1) 0..1 arrays with the difference between each 2 X 2 subblock maximum and minimum lexicographically nondecreasing rowwise and columnwise.

208, 2476, 28962, 335898, 3886120, 44920240, 519099694, 5998218844, 69307887110, 800828757910, 9253279485850, 106918144830246, 1235398494858302, 14274558937627814, 164937087638756238, 1905785172348833784

Offset

1,1

Comments

Column 3 of A235449.

Links

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

Formula

Empirical: a(n) = 17*a(n-1) -56*a(n-2) -150*a(n-3) +801*a(n-4) +479*a(n-5) -4435*a(n-6) -871*a(n-7) +12987*a(n-8) +2167*a(n-9) -21439*a(n-10) -5739*a(n-11) +19164*a(n-12) +7862*a(n-13) -7875*a(n-14) -4449*a(n-15) +862*a(n-16) +716*a(n-17) -8*a(n-18) -32*a(n-19).

Example

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

Crossrefs

Cf. A235449.

Sequence in context: A236272 A184681 A235674 * A255074 A172967 A343507

Adjacent sequences: A235441 A235442 A235443 * A235445 A235446 A235447

Keyword

nonn

Author

R. H. Hardin, Jan 10 2014

Status

approved