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A260171
Number of (n+2)X(2+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000001 00000101 or 00010001
1
74, 167, 419, 1001, 2500, 6344, 15847, 39584, 99741, 250297, 626433, 1572166, 3946872, 9894451, 24814854, 62266809, 156182193, 391707889, 982630798, 2464919670, 6182653471, 15508493498, 38902275855, 97581089767, 244769200723
OFFSET
1,1
COMMENTS
Column 2 of A260177
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +5*a(n-3) +5*a(n-4) -3*a(n-5) +5*a(n-6) +9*a(n-7) -5*a(n-8) -5*a(n-9) +4*a(n-10) -17*a(n-11) -14*a(n-12) +4*a(n-13) -4*a(n-14) -4*a(n-15) for n>16
EXAMPLE
Some solutions for n=4
..0..1..0..0....1..0..0..0....1..0..0..0....0..0..1..0....0..0..0..1
..0..0..0..0....0..0..0..1....0..1..0..0....0..0..0..1....0..0..1..0
..0..1..0..0....1..0..0..0....0..0..0..0....1..0..0..0....0..0..0..0
..1..0..0..0....0..0..0..0....0..1..0..0....0..0..0..0....1..0..0..0
..0..0..0..1....0..0..1..0....1..0..0..0....0..0..1..0....0..1..0..0
..0..0..1..0....0..0..0..1....0..0..0..0....0..1..0..0....0..0..1..0
CROSSREFS
Sequence in context: A044706 A217991 A105053 * A044406 A044787 A204370
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 17 2015
STATUS
approved