A207120 Number of nX5 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically

14, 196, 896, 4096, 12288, 36864, 87744, 208849, 428666, 879844, 1628368, 3013696, 5166336, 8856576, 14311584, 23126481, 35653926, 54967396, 81554000, 121000000, 173888000, 249892864, 349562304, 488984769, 668387538, 913611076, 1224032096

Offset

1,1

Comments

Column 5 of A207123

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)

Example

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

Crossrefs

Sequence in context: A207245 A208166 A207065 * A207963 A207502 A209654

Adjacent sequences: A207117 A207118 A207119 * A207121 A207122 A207123

Keyword

nonn

Author

R. H. Hardin Feb 15 2012

Status

approved