A208424 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 0 1 1 vertically

25, 625, 2625, 26375, 161975, 1297475, 8948825, 67061525, 479579725, 3521095775, 25468906525, 185793853675, 1348779310025, 9818938648875, 71365135739875, 519177351902675, 3774912413288375, 27456054751647025, 199657967390334825

Offset

1,1

Comments

Row 7 of A208420

Links

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

Formula

Empirical: a(n) = 52*a(n-2) +80*a(n-3) -477*a(n-4) -656*a(n-5) +1489*a(n-6) +1910*a(n-7) -1775*a(n-8) -2192*a(n-9) +812*a(n-10) +984*a(n-11) -120*a(n-12) -144*a(n-13)

Example

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

Crossrefs

Sequence in context: A208106 A207727 A207912 * A207784 A207597 A207023

Adjacent sequences: A208421 A208422 A208423 * A208425 A208426 A208427

Keyword

nonn

Author

R. H. Hardin Feb 26 2012

Status

approved