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A228664 Number of 5 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally. 1
16, 29, 574, 2228, 24109, 128740, 1096624, 6780585, 51990406, 344168764, 2516149353, 17192729316, 122982062328, 852741876277, 6038989672654, 42158071124804, 297183800090933, 2081125389730084, 14639300678885312 (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*(16 - 35*x - 86*x^2 + 162*x^3 + 29*x^4 - 66*x^5) / (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:

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

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

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

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

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

CROSSREFS

Row 5 of A228660.

Sequence in context: A054314 A222545 A115278 * A217715 A064634 A255265

Adjacent sequences:  A228661 A228662 A228663 * A228665 A228666 A228667

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 29 2013

STATUS

approved

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Last modified October 3 22:17 EDT 2022. Contains 357237 sequences. (Running on oeis4.)