A261706 Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000101 or 00000111.

172, 270, 468, 662, 1168, 2372, 3700, 6158, 11812, 19350, 31112, 58428, 98160, 157340, 290888, 493946, 796540, 1451708, 2482588, 4029944, 7257136, 12470954, 20367532, 36325296, 62623576, 102859784, 181987616, 314402990, 519129804

Offset

1,1

Comments

Column 3 of A261709.

Links

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

Formula

Empirical: a(n) = 4*a(n-3) +3*a(n-6) +4*a(n-7) -2*a(n-9) +4*a(n-11) -8*a(n-13) +10*a(n-14) for n>20.

Example

Some solutions for n=7
..0..0..0..0..1....1..0..0..0..0....1..0..1..0..0....1..0..0..0..0
..1..0..0..0..0....0..0..0..0..0....0..1..0..0..0....0..1..0..0..1
..1..1..0..0..1....1..0..0..1..0....0..0..0..0..0....1..0..0..0..0
..1..0..0..0..0....0..0..0..0..1....0..0..0..0..1....0..0..0..0..1
..0..0..0..0..1....0..0..0..0..0....1..0..0..1..0....1..0..0..1..0
..1..0..0..1..0....0..1..0..0..1....0..0..0..0..0....0..0..0..0..0
..0..0..0..0..0....1..0..0..0..0....1..0..0..0..0....0..0..0..0..0
..0..0..0..0..0....0..0..0..0..0....0..0..0..1..0....0..0..1..0..0
..0..1..0..0..1....1..0..0..1..0....0..0..0..0..1....0..1..1..1..0

Crossrefs

Cf. A261709.

Sequence in context: A067356 A230371 A056132 * A043387 A246475 A202641

Adjacent sequences: A261703 A261704 A261705 * A261707 A261708 A261709

Keyword

nonn

Author

R. H. Hardin, Aug 28 2015

Status

approved