A250804 Number of (7+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

1970, 9956, 37986, 124366, 361344, 968942, 2437366, 5849556, 13519146, 30351918, 66573728, 143373294, 304256334, 638165212, 1326004914, 2734630046, 5605754032, 11435981086, 23239612118, 47079690548, 95137712202, 191866743358

Offset

1,1

Comments

Row 7 of A250797

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -4*a(n-2) -17*a(n-3) +29*a(n-4) +16*a(n-5) -56*a(n-6) +6*a(n-7) +49*a(n-8) -19*a(n-9) -20*a(n-10) +11*a(n-11) +3*a(n-12) -2*a(n-13)

Example

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

Crossrefs

Sequence in context: A289561 A256738 A252012 * A205210 A183692 A206218

Adjacent sequences: A250801 A250802 A250803 * A250805 A250806 A250807

Keyword

nonn

Author

R. H. Hardin, Nov 27 2014

Status

approved