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A261288
Number of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00010101 or 01010101.
1
166, 233, 504, 1147, 2586, 6034, 14106, 32496, 75202, 175008, 405940, 940390, 2182098, 5064284, 11745648, 27244774, 63209588, 146635614, 340152614, 789099398, 1830590414, 4246594798, 9851282946, 22853254768, 53015328992
OFFSET
1,1
COMMENTS
Column 4 of A261292.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -2*a(n-2) +6*a(n-3) -a(n-4) +4*a(n-5) +a(n-6) -2*a(n-8) +2*a(n-9) -2*a(n-10) -4*a(n-11) -9*a(n-12) +4*a(n-13) -6*a(n-14) -2*a(n-16) -a(n-19) +3*a(n-20) -3*a(n-21) -a(n-24) for n>28
EXAMPLE
Some solutions for n=4
..0..1..0..1..0..1....0..0..1..0..1..0....0..1..0..1..0..1....0..1..0..1..0..1
..0..0..1..0..1..0....0..1..0..1..0..1....0..0..1..0..1..0....1..0..0..0..1..0
..0..1..0..0..0..1....1..0..1..0..1..0....0..1..0..1..0..1....0..1..0..1..0..1
..1..0..1..0..1..0....0..1..0..1..0..0....1..0..1..0..1..0....1..0..1..0..1..0
..0..1..0..1..0..1....1..0..1..0..1..0....0..1..0..1..0..1....0..0..0..1..0..1
..0..0..1..0..1..0....0..1..0..1..0..1....1..0..1..0..1..0....0..0..1..0..0..0
CROSSREFS
Cf. A261292.
Sequence in context: A015982 A065210 A261261 * A038007 A020361 A256643
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 14 2015
STATUS
approved