A317763 Number of nX7 0..1 arrays with every element unequal to 0, 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

64, 190, 196, 232, 302, 425, 639, 1012, 1663, 2801, 4792, 8278, 14385, 25088, 43852, 76756, 134466, 235697, 413288, 724863, 1271539, 2230756, 3913889, 6867349, 12050002, 21144516, 37103735, 65109496, 114255232, 200498730, 351843854

Offset

1,1

Comments

Column 7 of A317764.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) -a(n-4) +a(n-5) -a(n-6) +a(n-7) for n>11

Example

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

Crossrefs

Cf. A317764.

Sequence in context: A203448 A078093 A209371 * A318342 A318074 A202332

Adjacent sequences: A317760 A317761 A317762 * A317764 A317765 A317766

Keyword

nonn

Author

R. H. Hardin, Aug 06 2018

Status

approved