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A260923
Number of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 00101011 or 01010101
1
186, 279, 896, 2208, 4522, 10617, 25690, 58606, 134296, 314471, 729920, 1686078, 3909750, 9081515, 21033032, 48765365, 113054330, 262238504, 607643220, 1409411303, 3266491942, 7576260468, 17557722330, 40724481666, 94379231110
OFFSET
1,1
COMMENTS
Column 4 of A260927
LINKS
FORMULA
Empirical: a(n) = a(n-2) +18*a(n-4) +32*a(n-6) -7*a(n-8) -33*a(n-10) +13*a(n-12) +25*a(n-14) -28*a(n-16) +9*a(n-18) -a(n-20) for n>22
EXAMPLE
Some solutions for n=4
..0..0..1..0..1..0....1..0..0..1..1..0....1..0..0..1..0..1....0..1..0..1..1..0
..0..1..0..0..0..1....1..0..1..0..0..0....1..0..1..0..0..0....1..0..1..0..0..0
..1..0..1..0..1..0....0..1..0..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..1..0....1..0..1..0..1..0....1..0..1..0..1..0
..0..0..1..0..1..0....0..0..0..1..0..1....0..1..0..1..0..1....0..1..0..1..0..1
..1..1..0..1..0..1....0..1..1..0..0..1....1..0..1..0..0..1....0..0..1..0..1..0
CROSSREFS
Sequence in context: A189941 A362811 A363681 * A151701 A258276 A286006
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 04 2015
STATUS
approved