A207568 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

35, 1225, 4861, 23276, 160652, 738515, 3275898, 16648464, 77299468, 346860730, 1628437829, 7520074031, 34197531024, 157677790883, 726171154807, 3326887874211, 15303816884989, 70464546420156, 323991903658548

Offset

1,1

Comments

Row 7 of A207564

Links

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

Formula

Empirical: a(n) = 7*a(n-1) -12*a(n-2) +66*a(n-3) -355*a(n-4) +267*a(n-5) -845*a(n-6) +5223*a(n-7) +2042*a(n-8) -38*a(n-9) -35986*a(n-10) -32364*a(n-11) +462*a(n-12) +151576*a(n-13) +113718*a(n-14) -7212*a(n-15) -265050*a(n-16) -171750*a(n-17) +35538*a(n-18) +249492*a(n-19) +31110*a(n-20) -88254*a(n-21) -112194*a(n-22) +56598*a(n-23) +69082*a(n-24) +41276*a(n-25) -31470*a(n-26) -11664*a(n-27) -1085*a(n-28) +5229*a(n-29) -2218*a(n-30) -420*a(n-31) -959*a(n-32) +257*a(n-33) -65*a(n-34) -33*a(n-35) +32*a(n-37)

Example

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

Crossrefs

Sequence in context: A208844 A207665 A208006 * A209649 A207756 A207937

Adjacent sequences: A207565 A207566 A207567 * A207569 A207570 A207571

Keyword

nonn

Author

R. H. Hardin, Feb 18 2012

Status

approved