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A058975
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Total number of flats in the lattice of contractions of the n-cube. Also number of partitions of vertex set of n-cube into blocks all of which induce connected subgraphs.
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0
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OFFSET
| 0,2
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REFERENCES
| J. N. Cooper, unpublished.
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EXAMPLE
| There are twelve contractions of the 2-cube, also known as the 4-cycle. The edge sets along which the contractions occur are: no edges, any one of the four single edges, one of two opposite pairs, one of four pairs of intersecting edges and all edges.
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CROSSREFS
| Sequence in context: A129933 A064320 A112373 * A057120 A112512 A006751
Adjacent sequences: A058972 A058973 A058974 * A058976 A058977 A058978
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KEYWORD
| hard,nonn,nice
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AUTHOR
| Joshua N. Cooper (jcooper(AT)math.ucsd.edu), Jan 15 2001
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