A250803 Number of (6+1)X(n+1) 0..1 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

816, 3646, 12706, 38676, 105954, 270598, 653880, 1517666, 3411886, 7486456, 16113534, 34166562, 71587660, 148595086, 306145338, 627018812, 1278150458, 2595669838, 5255451696, 10615144698, 21399536646, 43073623696, 86592277446

Offset

1,1

Comments

Row 6 of A250797

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -17*a(n-3) +12*a(n-4) +28*a(n-5) -28*a(n-6) -22*a(n-7) +27*a(n-8) +8*a(n-9) -12*a(n-10) -a(n-11) +2*a(n-12)

Example

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

Crossrefs

Sequence in context: A272606 A235976 A015159 * A251205 A064583 A279441

Adjacent sequences: A250800 A250801 A250802 * A250804 A250805 A250806

Keyword

nonn

Author

R. H. Hardin, Nov 27 2014

Status

approved