A260099 Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000101 or 00010101.

48, 85, 206, 472, 1116, 2575, 6068, 14096, 33044, 76925, 180064, 419884, 981640, 2290567, 5352572, 12495004, 29189140, 68152069, 159185904, 371714924, 868161704, 2027353439, 4734819476, 11057193964, 25823175228, 60305591933

Offset

1,1

Links

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

Formula

Empirical: a(n) = 2*a(n-2) + 2*a(n-3) + 11*a(n-4) + 6*a(n-5) + 2*a(n-6) + 6*a(n-7) - 8*a(n-8) + 2*a(n-9) for n>10.

Empirical g.f.: x*(48 + 85*x + 110*x^2 + 206*x^3 + 6*x^4 - 4*x^5 + 20*x^6 - 172*x^7 + 112*x^8 - 20*x^9) / (1 - 2*x^2 - 2*x^3 - 11*x^4 - 6*x^5 - 2*x^6 - 6*x^7 + 8*x^8 - 2*x^9). - Colin Barker, Dec 28 2018

Example

Some solutions for n=4:
..0..0..0....0..0..0....1..0..1....0..1..0....1..0..1....0..1..0....0..0..1
..1..0..1....1..0..1....0..1..0....0..0..1....0..0..0....0..0..1....0..0..0
..0..1..0....0..1..0....1..0..0....0..1..0....0..0..1....0..0..0....0..0..1
..0..0..0....1..0..0....0..0..0....0..0..0....0..1..0....1..0..1....0..0..0
..0..0..0....0..0..0....1..0..0....0..0..0....1..0..1....0..1..0....1..0..1
..1..0..0....1..0..0....0..0..0....0..1..0....0..0..0....1..0..0....0..1..0

Crossrefs

Column 1 of A260106.

Sequence in context: A333814 A062902 A260106 * A224546 A247720 A204647

Adjacent sequences: A260096 A260097 A260098 * A260100 A260101 A260102

Keyword

nonn

Author

R. H. Hardin, Jul 16 2015

Status

approved