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A167243
Number of ways to partition an n X 3 grid into 3 connected equal-area regions.
2
1, 3, 10, 23, 56, 132, 259, 546, 1095, 2043, 3908, 7379, 13208, 24194, 43819, 76790, 136489, 241311, 416152, 726073, 1261696, 2153026, 3706393, 6364842, 10775173, 18374181
OFFSET
1,2
EXAMPLE
All solutions for n=4
...1.1.2...1.1.2...1.1.2...1.1.2...1.1.2...1.1.2...1.1.1...1.1.1...1.1.1
...1.2.2...1.2.2...1.1.2...1.1.2...1.3.2...3.1.2...1.2.2...1.2.2...1.2.2
...1.2.3...1.3.2...3.2.2...3.3.2...1.3.2...3.1.2...2.2.3...3.2.2...3.3.2
...3.3.3...3.3.3...3.3.3...3.3.2...3.3.2...3.3.2...3.3.3...3.3.3...3.3.2
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...1.1.1...1.1.1...1.1.1...1.1.1...1.1.1...1.1.1...1.1.1...1.2.2...1.2.2
...1.2.3...2.2.1...2.2.1...2.2.1...2.1.3...2.1.3...2.3.1...1.2.2...1.2.2
...2.2.3...2.2.3...2.3.3...3.2.2...2.2.3...2.3.3...2.3.3...1.1.3...1.3.3
...2.3.3...3.3.3...2.3.3...3.3.3...2.3.3...2.2.3...2.2.3...3.3.3...1.3.3
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...1.2.2...1.2.2...1.2.2...1.2.2...1.2.3
...1.2.3...1.1.2...1.1.2...1.3.2...1.2.3
...1.2.3...1.3.2...3.1.2...1.3.2...1.2.3
...1.3.3...3.3.3...3.3.3...1.3.3...1.2.3
CROSSREFS
Cf. A167242.
Sequence in context: A294503 A080204 A115982 * A316403 A185828 A134438
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 31 2009
STATUS
approved