A185527 Number of (n+2)X4 binary arrays with each 3X3 subblock nonsingular

726, 4362, 25854, 150234, 886926, 5221098, 30631134, 180225834, 1059790686, 6228272058, 36622083390, 215312392794, 1265757881262, 7441726142490, 43750907888814, 257212915031082, 1512188713814286, 8890318949201610

Offset

1,1

Comments

Column 2 of A185534

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=3*a(n-1)+8*a(n-2)+77*a(n-3)-79*a(n-4)-180*a(n-5)-1228*a(n-6)+48*a(n-7)+232*a(n-8)+4208*a(n-9)-1184*a(n-10)-1664*a(n-11)-6144*a(n-12)

Example

Some solutions for 6X4
..1..0..0..1....0..0..1..1....0..1..1..0....1..0..0..1....1..0..1..1
..0..0..1..0....1..0..0..1....0..0..1..1....0..0..1..0....0..1..1..0
..0..1..0..1....0..1..0..1....1..0..1..0....0..1..1..0....1..1..0..1
..1..0..0..1....1..1..1..0....1..1..1..1....1..1..0..1....1..0..0..1
..0..1..1..0....1..0..0..1....0..1..1..0....1..0..0..1....0..1..1..1
..0..0..1..0....0..1..0..1....0..1..0..0....0..1..1..1....1..0..1..0

Crossrefs

Sequence in context: A002769 A252617 A216618 * A306450 A259237 A084412

Adjacent sequences: A185524 A185525 A185526 * A185528 A185529 A185530

Keyword

nonn

Author

R. H. Hardin Jan 30 2011

Status

approved