

A229506


Number of defective 3colorings of an n X 4 0..2 array connected diagonally and antidiagonally with exactly one mistake, and colors introduced in rowmajor 0..2 order.


1



0, 288, 4032, 50112, 575424, 6298560, 66764736, 691581888, 7040530368, 70711413696, 702522486720, 6917780251584, 67615723104192, 656742815497152, 6344497107509184, 61004779879896000, 584181772129884096
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OFFSET

1,2


COMMENTS

Column 4 of A229510


LINKS

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


FORMULA

Empirical: a(n) = 18*a(n1)  81*a(n2) for n>4.
Conjectures from Colin Barker, Jun 16 2017: (Start)
G.f.: 288*x^2*(1  x)*(1  3*x) / (1  9*x)^2.
a(n) = 64*3^(2*n5)*(8*n  3) for n>2.
(End)


EXAMPLE

Some solutions for n=3
..0..1..1..1....0..0..0..0....0..0..0..0....0..1..2..2....0..0..1..2
..0..1..0..2....1..2..1..2....1..2..1..2....0..1..0..2....2..2..2..2
..0..1..0..1....0..0..1..1....1..0..1..1....2..2..0..1....0..0..1..0


CROSSREFS

Sequence in context: A235552 A033692 A182026 * A332429 A232340 A290028
Adjacent sequences: A229503 A229504 A229505 * A229507 A229508 A229509


KEYWORD

nonn


AUTHOR

R. H. Hardin, Sep 25 2013


STATUS

approved



