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A228686 Number of 5 X n binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally. 1
32, 99, 1277, 6160, 56549, 333517, 2644336, 17124415, 127116873, 859773376, 6193234393, 42741157353, 303661236672, 2115245880075, 14933039299621, 104468526402928, 735366366459485, 5154677670070421, 36235570461792016 (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) = 4*a(n-1) + 34*a(n-2) - 76*a(n-3) - 134*a(n-4) + 258*a(n-5) + 45*a(n-6) - 102*a(n-7).

Empirical g.f.: x*(32 - 29*x - 207*x^2 + 118*x^3 + 303*x^4 - 57*x^5 - 102*x^6) / (1 - 4*x - 34*x^2 + 76*x^3 + 134*x^4 - 258*x^5 - 45*x^6 + 102*x^7). - Colin Barker, Sep 12 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Row 5 of A228683.

Sequence in context: A218901 A192293 A188862 * A172517 A194645 A134845

Adjacent sequences:  A228683 A228684 A228685 * A228687 A228688 A228689

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 30 2013

STATUS

approved

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Last modified September 18 01:39 EDT 2021. Contains 347504 sequences. (Running on oeis4.)