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A205468 Number of (n+1) X 2 0..2 arrays with every 2 X 2 subblock having the same number of equal edges, and new values 0..2 introduced in row major order. 2
14, 48, 175, 677, 2709, 11143, 46709, 198483, 851317, 3674723, 15929949, 69254347, 301652741, 1315582371, 5742416845, 25079258843, 109571246421, 478835560339, 2092898539805, 9148671997707, 39994487184037, 174849254952131 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A205475.

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) - 21*a(n-2) - 11*a(n-3) + 66*a(n-4) - 6*a(n-5) - 36*a(n-6).

Empirical g.f.: x*(14 - 78*x + 37*x^2 + 264*x^3 - 105*x^4 - 180*x^5) / ((1 - x)*(1 - 3*x)*(1 - 2*x - 2*x^2)*(1 - 3*x - 6*x^2)). - Colin Barker, Mar 04 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A205475.

Sequence in context: A205753 A332606 A232826 * A195966 A337421 A345724

Adjacent sequences:  A205465 A205466 A205467 * A205469 A205470 A205471

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 27 2012

STATUS

approved

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Last modified December 5 12:24 EST 2021. Contains 349557 sequences. (Running on oeis4.)