A202528 Number of (n+2) X 6 binary arrays avoiding patterns 000 and 101 in rows, columns and nw-to-se diagonals

890, 2232, 4669, 9746, 21297, 45899, 97936, 210562, 453068, 972285, 2087770, 4485977, 9635163, 20693096, 44448598, 95473096, 205062389, 440453226, 946055233, 2032027019, 4364582616, 9374693066, 20135896348, 43249855813

Offset

1,1

Comments

Column 4 of A202532.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-3) -2*a(n-4) -2*a(n-5) +a(n-7) for n>8.

Empirical g.f.: x*(890 + 452*x + 205*x^2 - 1372*x^3 - 879*x^4 + 211*x^5 + 448*x^6 + 36*x^7) / ((1 - x)*(1 + x^2 - x^3)*(1 - x - 2*x^2 - x^3)). - Colin Barker, Jun 01 2018

Example

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

Crossrefs

Cf. A202532.

Sequence in context: A224338 A250513 A252577 * A006916 A128871 A110726

Adjacent sequences: A202525 A202526 A202527 * A202529 A202530 A202531

Keyword

nonn

Author

R. H. Hardin, Dec 20 2011

Status

approved