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A205584 Number of (n+1) X 3 0..2 arrays with no 2 X 2 subblock having the same number of equal edges as its horizontal or vertical neighbors, and new values 0..2 introduced in row major order. 1
74, 550, 4220, 32500, 248940, 1910922, 14668206, 112560786, 863863526, 6629842280, 50880821560, 390488098388, 2996825524800, 22999305690670, 176509524902826, 1354632729727342, 10396208030732474, 79786307537199012 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A205590.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +24*a(n-2) +82*a(n-3) +83*a(n-4) -107*a(n-5) +30*a(n-6) +250*a(n-7).

Empirical g.f.: 2*x*(37 + 164*x + 397*x^2 + 286*x^3 - 541*x^4 + 165*x^5 + 1125*x^6) / (1 - 3*x - 24*x^2 - 82*x^3 - 83*x^4 + 107*x^5 - 30*x^6 - 250*x^7). - Colin Barker, Jun 12 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Cf. A205590.

Sequence in context: A296025 A204362 A321114 * A280402 A250913 A186124

Adjacent sequences:  A205581 A205582 A205583 * A205585 A205586 A205587

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 29 2012

STATUS

approved

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Last modified March 5 11:57 EST 2021. Contains 341823 sequences. (Running on oeis4.)