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A228680 Number of nX5 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally. 1
13, 97, 809, 6737, 56549, 475809, 4008817, 33795201, 284980061, 2403420097, 20270798553, 170971640209, 1442058561397, 12163101107393, 102590452275041, 865306832676993, 7298499493581101, 61559793235182241, 519231197740651273 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A228683

LINKS

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

FORMULA

Empirical: a(n) = 12*a(n-1) -27*a(n-2) -32*a(n-3) +49*a(n-4) +20*a(n-5) -5*a(n-6).

Empirical: G.f. -x*(-13+59*x+4*x^2-64*x^3-15*x^4+5*x^5) / ( 1-12*x+27*x^2+32*x^3-49*x^4-20*x^5+5*x^6 ). - R. J. Mathar, Sep 02 2013

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A049294 A198480 A126508 * A158795 A075899 A006976

Adjacent sequences:  A228677 A228678 A228679 * A228681 A228682 A228683

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 30 2013

STATUS

approved

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Last modified January 20 11:11 EST 2020. Contains 331083 sequences. (Running on oeis4.)