A190028 Number of (n+2) X 6 binary arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.

415, 155, 274, 458, 578, 670, 790, 966, 1242, 1702, 2338, 3247, 4460, 6025, 8139, 11017, 14883, 20207, 27508, 37362, 50788, 69069, 93769, 127365, 173117, 235142, 319489, 434273, 590030, 801705, 1089569, 1480431, 2011558, 2733658, 3714513

Offset

1,1

Comments

Column 4 of A190033.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 2*a(n-1) -a(n-2) +a(n-3) -2*a(n-4) +a(n-5) +a(n-6) -a(n-7) for n>12.

Empirical g.f.: x*(415 - 675*x + 379*x^2 - 350*x^3 + 611*x^4 - 407*x^5 - 452*x^6 + 380*x^7 + 9*x^8 - 28*x^9 + 81*x^11) / ((1 - x)*(1 - x - x^3 + x^4 - x^6)). - Colin Barker, May 03 2018

Example

Some solutions for 4 X 6:
..1..0..0..0..0..0....0..0..0..0..0..1....0..0..0..0..1..0....0..0..0..0..0..0
..0..0..0..0..0..1....0..0..0..0..0..1....0..0..0..0..0..0....0..0..0..0..0..1
..0..0..0..0..0..0....1..0..0..0..0..1....1..0..0..0..0..0....1..0..0..0..0..0
..0..1..0..0..0..0....1..0..0..0..0..1....0..1..0..0..0..0....0..0..0..0..0..0

Crossrefs

Cf. A190033.

Sequence in context: A210304 A332141 A187864 * A184545 A096032 A166057

Adjacent sequences: A190025 A190026 A190027 * A190029 A190030 A190031

Keyword

nonn

Author

R. H. Hardin, May 04 2011

Status

approved