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A260835
Number of (n+2)X(2+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000011 or 00010101
1
82, 131, 288, 496, 796, 1645, 2976, 4890, 9332, 17659, 30090, 54846, 104380, 184549, 329454, 618800, 1121728, 1998197, 3692344, 6772932, 12142202, 22172787, 40769872, 73664484, 133728146, 245325455, 445857864, 808254626, 1477620470
OFFSET
1,1
COMMENTS
Column 2 of A260841
LINKS
FORMULA
Empirical: a(n) = a(n-1) +5*a(n-3) -a(n-4) -3*a(n-5) -5*a(n-6) +3*a(n-9) -2*a(n-10) -5*a(n-11) -2*a(n-12) -a(n-13) +5*a(n-14) -2*a(n-15) -2*a(n-17) +2*a(n-18) for n>19
EXAMPLE
Some solutions for n=4
..1..0..1..0....0..1..1..0....1..0..1..1....0..0..0..0....0..0..0..1
..0..1..0..1....0..0..0..0....0..0..0..0....0..0..0..0....0..0..1..0
..1..0..0..0....0..0..0..0....1..0..0..0....1..0..0..1....0..0..0..0
..0..1..0..0....1..1..0..0....0..0..0..1....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..1..0..0
..0..0..0..0....0..0..0..0....0..1..0..1....1..1..0..1....1..1..0..0
CROSSREFS
Sequence in context: A223088 A039547 A029704 * A173087 A264352 A044252
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 01 2015
STATUS
approved