A207366 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 1 vertically

18, 324, 1350, 5625, 15525, 42849, 95220, 211600, 409860, 793881, 1397088, 2458624, 4029760, 6604900, 10246590, 15896169, 23603040, 35046400, 50207520, 71927361, 100016433, 139074849, 188570070, 255680100, 339259830, 450161089, 586225710

Offset

1,1

Comments

Column 6 of A207368

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) +6*a(n-2) -14*a(n-3) -14*a(n-4) +42*a(n-5) +14*a(n-6) -70*a(n-7) +70*a(n-9) -14*a(n-10) -42*a(n-11) +14*a(n-12) +14*a(n-13) -6*a(n-14) -2*a(n-15) +a(n-16)

Example

Some solutions for n=4
..0..0..1..0..0..1....0..1..0..0..1..0....1..0..1..0..1..0....0..1..0..0..1..0
..0..1..0..1..0..0....0..0..1..0..0..1....0..1..0..1..0..1....0..0..1..0..1..0
..0..0..1..0..0..1....0..1..0..0..1..0....0..0..1..0..1..0....0..1..0..0..1..0
..0..1..0..1..0..0....0..0..1..0..0..1....0..1..0..1..0..1....0..0..1..0..1..0

Crossrefs

Sequence in context: A208423 A207783 A207022 * A187381 A207109 A207465

Adjacent sequences: A207363 A207364 A207365 * A207367 A207368 A207369

Keyword

nonn

Author

R. H. Hardin Feb 17 2012

Status

approved