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A184034
1/16 the number of (n+1) X 5 0..3 arrays with all 2 X 2 subblocks having the same four values.
2
91, 103, 124, 166, 244, 400, 700, 1300, 2476, 4828, 9484, 18796, 37324, 74380, 148300, 296140, 591436, 1182028, 2362444, 4723276, 9443404, 18883660, 37761100, 75515980, 151019596, 302026828, 604029004, 1208033356, 2416017484, 4831985740
OFFSET
1,1
COMMENTS
Column 4 of A184039.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) - 6*a(n-3) + 4*a(n-4).
Conjectures from Colin Barker, Apr 10 2018: (Start)
G.f.: x*(91 - 170*x - 185*x^2 + 340*x^3) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)).
a(n) = 9*2^(n/2-1) + 9*2^(n-1) + 76 for n even.
a(n) = 9*2^(n-1) + 3*2^((n+1)/2) + 76 for n odd.
(End)
EXAMPLE
Some solutions for 3 X 5:
..3..1..0..1..3....2..3..3..3..3....2..1..2..0..2....1..1..3..2..1
..0..2..3..2..0....3..0..2..0..2....3..0..3..1..3....3..2..1..1..3
..3..1..0..1..3....2..3..3..3..3....2..1..2..0..2....1..1..3..2..1
CROSSREFS
Cf. A184039.
Sequence in context: A020223 A288453 A344801 * A294742 A224981 A261260
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 08 2011
STATUS
approved