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A208015 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 0 1 1 vertically. 1
12, 144, 420, 1943, 5952, 16224, 55624, 181192, 545140, 1737120, 5591900, 17461000, 55016920, 175036148, 552196708, 1741059012, 5511897568, 17422085700, 55006038672, 173881945232, 549639384692, 1736473292204, 5487493400532 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A208013.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + 23*a(n-3) + 6*a(n-4) + 6*a(n-5) - 108*a(n-6) - 72*a(n-7) + 216*a(n-9) for n>11.

Empirical g.f.: x*(12 + 132*x + 276*x^2 + 1247*x^3 + 625*x^4 - 324*x^5 - 7377*x^6 - 9090*x^7 - 846*x^8 + 17064*x^9 + 7884*x^10) / (1 - x - 23*x^3 - 6*x^4 - 6*x^5 + 108*x^6 + 72*x^7 - 216*x^9). - Colin Barker, Jun 26 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A208013.

Sequence in context: A207457 A208120 A207370 * A208557 A183355 A267716

Adjacent sequences:  A208012 A208013 A208014 * A208016 A208017 A208018

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 22 2012

STATUS

approved

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Last modified January 19 22:12 EST 2022. Contains 350466 sequences. (Running on oeis4.)