A207407 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 1 0 vertically

14, 196, 966, 4761, 16284, 55696, 154580, 429025, 1033590, 2490084, 5404650, 11730625, 23481800, 47004736, 88175016, 165405321, 294131070, 523036900, 889299950, 1512043225, 2474485860, 4049540496, 6412154268, 10153182169

Offset

1,1

Comments

Row 7 of A207403

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +12*a(n-2) -26*a(n-3) -65*a(n-4) +156*a(n-5) +208*a(n-6) -572*a(n-7) -429*a(n-8) +1430*a(n-9) +572*a(n-10) -2574*a(n-11) -429*a(n-12) +3432*a(n-13) -3432*a(n-15) +429*a(n-16) +2574*a(n-17) -572*a(n-18) -1430*a(n-19) +429*a(n-20) +572*a(n-21) -208*a(n-22) -156*a(n-23) +65*a(n-24) +26*a(n-25) -12*a(n-26) -2*a(n-27) +a(n-28)

Example

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

Crossrefs

Sequence in context: A207502 A209654 A207074 * A207708 A207253 A208291

Adjacent sequences: A207404 A207405 A207406 * A207408 A207409 A207410

Keyword

nonn

Author

R. H. Hardin Feb 17 2012

Status

approved