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A207953 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 1 0 and 1 0 1 vertically 1
42, 1764, 14406, 117649, 524104, 2334784, 7513176, 24176889, 63380130, 166152100, 377999250, 859955625, 1762784400, 3613452544, 6837439440, 12937925025, 22975807530, 40801576036, 68811074046, 116048554281, 187501438872 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207949

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..1..0....1..0..1..0....1..0..0..0....1..1..0..0....1..0..1..0

..1..1..1..1....1..1..0..1....1..0..1..0....0..0..0..0....1..1..0..1

..1..1..1..1....1..1..0..1....1..1..1..0....0..0..0..0....1..1..0..1

..1..1..1..1....0..1..0..0....0..1..0..0....1..0..0..0....0..0..0..0

..1..1..1..0....0..0..0..0....0..0..0..0....1..1..1..0....0..0..0..0

..1..0..1..0....0..0..0..0....0..0..0..0....1..1..1..1....1..0..1..0

..1..0..0..0....0..0..0..0....1..0..0..0....0..1..0..1....1..1..1..0

CROSSREFS

Sequence in context: A207471 A207523 A207258 * A207862 A207812 A208286

Adjacent sequences:  A207950 A207951 A207952 * A207954 A207955 A207956

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 21 2012

STATUS

approved

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Last modified November 29 18:41 EST 2021. Contains 349416 sequences. (Running on oeis4.)