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A229406 Number of n X 2 0..3 arrays avoiding 11 horizontally, 22 vertically, 33 antidiagonally and 00 diagonally. 1
15, 163, 1756, 18712, 199595, 2127718, 22684613, 241841143, 2578301479, 27487534672, 293047669224, 3124213038091, 33307577031714, 355095715688893, 3785714221110283, 40359912854042611, 430281439964832908 (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) = 10*a(n-1) + 13*a(n-2) - 67*a(n-3) + 38*a(n-4) - 2*a(n-5).

Empirical g.f.: x*(15 + 13*x - 69*x^2 + 38*x^3 - 2*x^4) / (1 - 10*x - 13*x^2 + 67*x^3 - 38*x^4 + 2*x^5). - Colin Barker, Sep 15 2018

EXAMPLE

Some solutions for n=3:

..3..3....3..2....2..3....3..3....1..0....0..2....1..0....1..0....0..2....3..3

..2..2....3..0....1..2....2..0....3..0....3..3....3..2....1..0....1..3....1..3

..1..0....0..1....1..3....3..3....3..0....1..2....2..3....3..1....2..0....0..1

CROSSREFS

Column 2 of A229412.

Sequence in context: A016243 A164599 A016291 * A118093 A167615 A210326

Adjacent sequences:  A229403 A229404 A229405 * A229407 A229408 A229409

KEYWORD

nonn

AUTHOR

R. H. Hardin, Sep 22 2013

STATUS

approved

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Last modified December 4 22:42 EST 2021. Contains 349526 sequences. (Running on oeis4.)