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A206628 Number of (n+1) X 2 0..2 arrays with every 2 X 3 or 3 X 2 subblock having no more than four equal edges, and new values 0..2 introduced in row major order. 2
14, 121, 1085, 9729, 87238, 782246, 7014246, 62895364, 563970356, 5057011236, 45345224920, 406601711384, 3645917557848, 32692225503376, 293144754758096, 2628571347438864, 23569882170595936, 211346496672826976 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A206635.

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) + 8*a(n-2) + 6*a(n-3) for n>4.

Empirical g.f.: x*(14 + 9*x + 5*x^2 - 3*x^3) / (1 - 8*x - 8*x^2 - 6*x^3). - Colin Barker, Mar 04 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A206635.

Sequence in context: A249980 A206635 A163942 * A235710 A239544 A167567

Adjacent sequences:  A206625 A206626 A206627 * A206629 A206630 A206631

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 10 2012

STATUS

approved

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Last modified January 24 08:21 EST 2021. Contains 340398 sequences. (Running on oeis4.)