A202595 Number of (n+2) X 4 binary arrays avoiding patterns 001 and 000 in rows and columns.

510, 3150, 18160, 107510, 629790, 3704980, 21758550, 127872530, 751278240, 4414434310, 25937520830, 152401930300, 895465610130, 5261491036130, 30914921038320, 181646780968570, 1067301604632450, 6271142423909740

Offset

1,1

Comments

Column 2 of A202601.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +22*a(n-2) +12*a(n-3) -43*a(n-4) -8*a(n-5) +18*a(n-6) -a(n-8).

Empirical g.f.: 10*x*(51 + 213*x + 64*x^2 - 423*x^3 - 62*x^4 + 179*x^5 - x^6 - 10*x^7) / (1 - 2*x - 22*x^2 - 12*x^3 + 43*x^4 + 8*x^5 - 18*x^6 + x^8). - Colin Barker, Jun 01 2018

Example

Some solutions for n=3:
..0..1..1..1....1..1..0..1....1..0..1..1....0..1..1..0....1..1..1..1
..1..1..0..0....1..1..1..1....0..1..1..1....1..0..1..1....1..1..0..0
..1..1..1..1....1..1..0..0....1..0..1..0....1..1..0..1....1..0..1..1
..1..1..0..1....1..1..1..1....0..1..0..1....1..1..1..0....0..1..1..1
..1..1..0..1....0..1..1..1....1..0..1..0....1..1..1..1....0..1..1..0

Crossrefs

Cf. A202601.

Sequence in context: A249551 A248790 A252877 * A252882 A252883 A196674

Adjacent sequences: A202592 A202593 A202594 * A202596 A202597 A202598

Keyword

nonn

Author

R. H. Hardin, Dec 21 2011

Status

approved