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A231992 Number of (n+1) X (2+1) 0..1 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to one. 1
6, 32, 156, 800, 4000, 20228, 101808, 513400, 2586980, 13039568, 65717568, 331222548, 1669362032, 8413644600, 42404958708, 213722166160, 1077165216736, 5428941217444, 27362005944240, 137905229697144, 695045979384260 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) + 12*a(n-2) - 5*a(n-3) - 19*a(n-4) + 2*a(n-5) + 4*a(n-6).

Empirical g.f.: 2*x*(1 + x)*(3 + 4*x - 10*x^2 - x^3 + 2*x^4) / (1 - 3*x - 12*x^2 + 5*x^3 + 19*x^4 - 2*x^5 - 4*x^6). - Colin Barker, Oct 01 2018

EXAMPLE

Some solutions for n=7:

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

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

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

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

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

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

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

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

CROSSREFS

Column 2 of A231997.

Sequence in context: A242542 A046725 A232331 * A292044 A006668 A232494

Adjacent sequences:  A231989 A231990 A231991 * A231993 A231994 A231995

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 16 2013

STATUS

approved

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Last modified September 19 04:30 EDT 2019. Contains 327187 sequences. (Running on oeis4.)