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A228479 Number of n X 5 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or antidiagonally. 1
5, 19, 127, 728, 4354, 25699, 152373, 902042, 5342712, 31639786, 187379548, 1109702480, 6571916787, 38920392611, 230495519461, 1365047364511, 8084124028133, 47876038862427, 283532896714060, 1679146925634733 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Same recurrences as A228285 except in addition this smaller one for this column.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) + 15*a(n-2) + 16*a(n-3) - 11*a(n-4) - 20*a(n-5) + 19*a(n-6) - 8*a(n-7) + a(n-9).

Empirical g.f.: x*(5 + 4*x - 5*x^2 - 18*x^3 + 16*x^4 - 6*x^5 + x^7) / (1 - 3*x - 15*x^2 - 16*x^3 + 11*x^4 + 20*x^5 - 19*x^6 + 8*x^7 - x^9). - Colin Barker, Sep 11 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 5 of A228482.

Sequence in context: A209111 A328060 A297389 * A187018 A193287 A027269

Adjacent sequences:  A228476 A228477 A228478 * A228480 A228481 A228482

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 22 2013

STATUS

approved

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Last modified October 20 22:44 EDT 2019. Contains 328291 sequences. (Running on oeis4.)