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A183399 Half the number of n X 3 binary arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors. 1
4, 2, 6, 32, 110, 450, 1680, 6498, 24794, 95048, 364030, 1394450, 5342640, 20467202, 78415506, 300419072, 1150965830, 4409544050, 16893761040, 64722982898, 247965235594, 949998793608, 3639613683310, 13944005214050, 53421954623280 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A183402.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 5*a(n-1) - 23*a(n-3) + 15*a(n-4) + 40*a(n-5) - 46*a(n-6) + 20*a(n-8) - 8*a(n-9) for n>10.

Empirical g.f.: 2*x*(2 - 9*x - 2*x^2 + 47*x^3 - 32*x^4 - 76*x^5 + 90*x^6 - 40*x^8 + 16*x^9) / ((1 - 5*x + 5*x^2 - 2*x^3)*(1 - 5*x^2 + 10*x^4 - 4*x^6)). - Colin Barker, Mar 28 2018

EXAMPLE

Some solutions with a(1,1)=0 for 4 X 3:

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

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

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

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

CROSSREFS

Cf. A183402.

Sequence in context: A132996 A019182 A019105 * A248250 A176385 A155829

Adjacent sequences:  A183396 A183397 A183398 * A183400 A183401 A183402

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 04 2011

STATUS

approved

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Last modified May 26 22:57 EDT 2019. Contains 323597 sequences. (Running on oeis4.)