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A208080 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 0 1 0 vertically. 1
15, 225, 1785, 16065, 139605, 1228095, 10751415, 94313535, 826627095, 7247786265, 63537791985, 557042877105, 4883512293885, 42813574729335, 375342984092895, 3290607987017295, 28848520578042495, 252912991131598545 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A208078.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +40*a(n-2) +24*a(n-3) -70*a(n-4) -28*a(n-5) +36*a(n-6) -a(n-8).

Empirical g.f.: 15*x*(1 - x)*(1 + 12*x + 31*x^2 + 2*x^3 - 25*x^4 + 2*x^5 + x^6) / (1 - 4*x - 40*x^2 - 24*x^3 + 70*x^4 + 28*x^5 - 36*x^6 + x^8). - Colin Barker, Jan 20 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Sequence in context: A207423 A207738 A221966 * A224264 A223921 A224191

Adjacent sequences:  A208077 A208078 A208079 * A208081 A208082 A208083

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 23 2012

STATUS

approved

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Last modified June 23 08:56 EDT 2021. Contains 345395 sequences. (Running on oeis4.)