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A166796 Number of nX2 1..3 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nondecreasing order. 1
0, 6, 26, 69, 146, 270, 456, 721, 1084, 1566, 2190, 2981, 3966, 5174, 6636, 8385, 10456, 12886, 15714, 18981, 22730, 27006, 31856, 37329, 43476, 50350, 58006, 66501, 75894, 86246, 97620, 110081, 123696, 138534, 154666, 172165, 191106, 211566, 233624 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

R. H. Hardin, Table of n, a(n) for n=1..83

FORMULA

Empirical: a(n)=(n^4+8*n^3+11*n^2-32*n+12)/12

EXAMPLE

All solutions for n=3

...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.2...1.1...1.1

...2.2...2.2...2.2...1.2...1.2...1.2...1.3...1.3...3.2...3.2...3.3...2.2...2.2

...2.3...3.2...3.3...1.3...3.2...3.3...1.3...3.3...3.2...3.3...3.3...2.3...3.3

------

...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.1...1.3...1.3...1.3...1.3...1.3

...2.3...2.3...1.2...1.2...1.2...1.1...1.3...1.3...2.2...2.3...2.3...1.3...1.3

...2.3...3.3...1.3...3.2...3.3...2.3...2.2...2.3...2.2...2.3...3.3...2.2...2.3

CROSSREFS

Sequence in context: A136892 A190095 A135036 * A001701 A175898 A094162

Adjacent sequences:  A166793 A166794 A166795 * A166797 A166798 A166799

KEYWORD

nonn

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Oct 21 2009

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Last modified February 17 18:38 EST 2012. Contains 206074 sequences.