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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 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified March 30 12:10 EDT 2020. Contains 333125 sequences. (Running on oeis4.)