A260133 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.

138, 342, 1162, 2966, 7698, 22522, 61914, 165954, 462030, 1279574, 3493270, 9617162, 26547878, 72931662, 200533394, 552344746, 1519650534, 4179817642, 11503670758, 31655891034, 87092868954, 239649098010, 659447987986

Offset

1,1

Links

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

Formula

Empirical: a(n) = a(n-1) + a(n-2) + 10*a(n-3) + 4*a(n-4) - 2*a(n-5) - 12*a(n-6) - 5*a(n-7) - 4*a(n-8) + 4*a(n-9) for n>10.

Empirical g.f.: 2*x*(69 + 102*x + 341*x^2 + 41*x^3 - 201*x^4 - 427*x^5 - 137*x^6 - 104*x^7 + 144*x^8 - 12*x^9) / (1 - x - x^2 - 10*x^3 - 4*x^4 + 2*x^5 + 12*x^6 + 5*x^7 + 4*x^8 - 4*x^9).- Colin Barker, Dec 28 2018

Example

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

Crossrefs

Column 3 of A260138.

Sequence in context: A202441 A187206 A168531 * A317579 A281592 A213963

Adjacent sequences: A260130 A260131 A260132 * A260134 A260135 A260136

Keyword

nonn

Author

R. H. Hardin, Jul 17 2015

Status

approved