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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.
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 28 2015
STATUS
approved