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A260975
Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00001001 or 00100101
1
204, 239, 372, 732, 1288, 2576, 4688, 8760, 15964, 30062, 55496, 105078, 192148, 361876, 663360, 1248880, 2301984, 4312846, 7974836, 14889918, 27581092, 51446550, 95444100, 177936588, 330029564, 614889132, 1141497232, 2126263226
OFFSET
1,1
COMMENTS
Column 3 of A260980
LINKS
FORMULA
Empirical: a(n) = 8*a(n-4) +6*a(n-5) +10*a(n-7) +5*a(n-8) -24*a(n-9) -4*a(n-10) -26*a(n-11) +39*a(n-12) -a(n-14) for n>18
EXAMPLE
Some solutions for n=4
..0..1..0..0..1....1..0..0..1..0....0..0..0..1..0....0..1..0..0..1
..0..0..1..0..0....0..0..1..0..0....0..0..0..0..0....0..0..1..0..0
..1..0..0..0..0....1..0..0..0..1....1..0..0..0..0....1..0..0..0..1
..0..1..0..0..0....0..1..0..0..0....0..0..0..1..0....0..0..0..1..0
..0..0..0..1..0....0..0..0..0..0....0..1..0..0..1....0..1..0..0..0
..1..0..0..0..1....0..0..0..0..1....0..0..1..0..0....0..0..1..0..1
CROSSREFS
Sequence in context: A198913 A224983 A138605 * A271643 A108877 A163393
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 06 2015
STATUS
approved