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A185480
Number of (n+1)X3 binary arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant
1
30, 148, 684, 3262, 15402, 73094, 346356, 1642258, 7785218, 36909314, 174980330, 829558720, 3932814406, 18644913662, 88392840864, 419057759044, 1986692502674, 9418623349146, 44652337958296, 211690309447022, 1003593296864578
OFFSET
1,1
COMMENTS
Column 2 of A185487
LINKS
FORMULA
Empirical: a(n)=8*a(n-1)-17*a(n-2)+a(n-3)+43*a(n-4)-71*a(n-5)+48*a(n-6)-9*a(n-7)-4*a(n-8)+10*a(n-9)-2*a(n-10) for n>12
EXAMPLE
Some solutions for 5X3
..0..0..0....1..0..1....1..0..0....0..1..1....0..1..1....1..1..0....1..0..1
..0..0..0....1..0..0....0..0..0....0..0..0....1..1..0....1..1..1....1..0..0
..1..0..1....1..0..0....1..0..0....1..1..0....0..0..0....0..0..1....1..0..1
..0..0..0....1..0..1....1..1..0....1..1..0....0..1..0....1..0..1....1..0..0
..1..1..0....1..0..1....0..1..1....0..1..1....0..1..0....0..0..1....1..0..0
CROSSREFS
Sequence in context: A126417 A135175 A186895 * A316459 A342483 A206040
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 28 2011
STATUS
approved