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A188608
Number of 3Xn binary arrays without the pattern 1 1 0 diagonally, vertically, antidiagonally or horizontally
1
7, 49, 211, 847, 3282, 12405, 45860, 167525, 605878, 2177496, 7787333, 27757367, 98687854, 350247594, 1241371867, 4395505741, 15552531864, 55000200159, 194426956404, 687105218857, 2427709127594, 8576325199050, 30293865359314
OFFSET
1,1
COMMENTS
Row 3 of A188607
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) + a(n-2) - 56*a(n-3) + 38*a(n-4) + 201*a(n-5) - 139*a(n-6) - 386*a(n-7) + 109*a(n-8) + 450*a(n-9) + 195*a(n-10) - 288*a(n-11) - 391*a(n-12) + 11*a(n-13) + 219*a(n-14) + 110*a(n-15) - 13*a(n-16) - 53*a(n-17) - 21*a(n-18) + 5*a(n-19) + 3*a(n-20) for n>21
EXAMPLE
Some solutions for 3X3
..0..0..0....0..1..1....1..0..1....0..0..1....0..0..0....0..0..1....0..0..1
..0..0..0....0..0..0....1..0..0....0..0..0....0..1..1....0..0..1....1..0..0
..0..1..0....0..0..0....1..0..1....0..0..0....0..0..1....1..0..1....1..0..1
CROSSREFS
Sequence in context: A294292 A015953 A206931 * A188601 A206866 A206872
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 05 2011
STATUS
approved