A235768 Number of (n+1)X(3+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

120, 628, 2994, 12417, 47501, 166904, 552444, 1724793, 5144350, 14696712, 40503441, 107993795, 279771656, 706134649, 1741178487, 4204576953, 9961571579, 23204492256, 53213406141, 120352868718, 268716844980, 593201019964

Offset

1,1

Comments

Column 3 of A235772

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +22*a(n-2) -106*a(n-3) -206*a(n-4) +1310*a(n-5) +970*a(n-6) -10018*a(n-7) -1220*a(n-8) +53030*a(n-9) -14210*a(n-10) -205870*a(n-11) +113050*a(n-12) +605570*a(n-13) -469970*a(n-14) -1374070*a(n-15) +1346965*a(n-16) +2422430*a(n-17) -2874380*a(n-18) -3308560*a(n-19) +4711492*a(n-20) +3445592*a(n-21) -6005504*a(n-22) -2628928*a(n-23) +5959072*a(n-24) +1319360*a(n-25) -4565120*a(n-26) -254464*a(n-27) +2650240*a(n-28) -198400*a(n-29) -1127936*a(n-30) +203264*a(n-31) +332032*a(n-32) -88576*a(n-33) -60416*a(n-34) +20480*a(n-35) +5120*a(n-36) -2048*a(n-37)

Example

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

Crossrefs

Sequence in context: A090216 A265041 A280425 * A179963 A229568 A342923

Adjacent sequences: A235765 A235766 A235767 * A235769 A235770 A235771

Keyword

nonn

Author

R. H. Hardin, Jan 15 2014

Status

approved