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A166762
Number of nX3 1..3 arrays containing at least one of each value, and all equal values connected.
0
6, 174, 1548, 8100, 32208, 108456, 327042, 912330, 2403570, 6063738, 14792208, 35140296, 81722988, 186803940, 420988854, 937659294, 2067934782, 4522786278, 9821642100, 21198358092, 45510675048, 97254168192, 206980215882
OFFSET
1,1
FORMULA
Empirical: a(n) = 11*a(n-1) - 53*a(n-2) + 147*a(n-3) - 259*a(n-4) + 301*a(n-5) - 231*a(n-6) + 113*a(n-7) - 32*a(n-8) + 4*a(n-9).
EXAMPLE
Some solutions for n=4
...2.2.2...2.2.3...1.1.1...1.1.2...1.2.2...1.1.1...2.2.3...2.3.3...3.3.3
...1.1.2...3.2.3...3.1.1...2.2.2...3.3.2...1.3.3...2.3.3...2.3.1...3.1.1
...3.1.2...3.3.3...2.2.1...3.2.2...3.3.2...1.1.1...1.1.3...2.3.1...2.1.2
...3.1.1...3.1.3...1.1.1...3.3.3...2.2.2...2.2.1...1.1.1...2.1.1...2.2.2
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...1.1.2...2.2.2...1.1.1...1.1.1...3.3.3...3.3.3...2.2.2...3.3.1...2.1.3
...1.1.1...1.1.3...1.1.1...2.1.1...3.3.1...1.3.3...3.2.1...2.3.1...1.1.3
...1.3.3...3.3.3...2.3.1...2.1.3...2.3.3...1.1.3...3.3.1...2.3.3...1.1.1
...1.1.3...3.3.3...2.3.1...1.1.3...2.2.2...1.2.2...1.1.1...2.3.3...1.1.1
CROSSREFS
Sequence in context: A266311 A323820 A317795 * A323279 A214801 A233225
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 21 2009
STATUS
approved