A202609 Number of (n+2) X 3 binary arrays avoiding patterns 001 and 010 in rows and columns.

108, 323, 1058, 3223, 9515, 28426, 84486, 249106, 734637, 2166526, 6380211, 18782449, 55296998, 162765970, 479038288, 1409873905, 4149367138, 12211531035, 35938252497, 105765419940, 311263342522, 916033572652, 2695845174863

Offset

1,1

Comments

Column 1 of A202616.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -5*a(n-2) +16*a(n-3) -35*a(n-4) +19*a(n-5) -48*a(n-6) +80*a(n-7) +12*a(n-8) +52*a(n-9) -92*a(n-10) -54*a(n-11) -52*a(n-12) +76*a(n-13) +43*a(n-14) +32*a(n-15) -27*a(n-16) -16*a(n-17) -11*a(n-18) +5*a(n-19) +2*a(n-21).

Example

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

Crossrefs

Cf. A202616.

Sequence in context: A138669 A304377 A202616 * A202100 A202492 A369420

Adjacent sequences: A202606 A202607 A202608 * A202610 A202611 A202612

Keyword

nonn

Author

R. H. Hardin, Dec 21 2011

Status

approved