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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
OFFSET
1,1
COMMENTS
Column 2 of A205590.
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 29 2012
STATUS
approved