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A121139
Numbers of isomers of unbranched a-4-catapolyheptagons - see Brunvoll reference for precise definition.
0
1, 3, 11, 48, 228, 1080, 5112, 23920, 110848
OFFSET
2,2
REFERENCES
J. Brunvoll, S. J. Cyvin and B. N. Cyvin, Isomer enumeration of polygonal systems..., J. Molec. Struct. (Theochem), 364 (1996), 1-13.
CROSSREFS
Sequence in context: A308538 A181278 A126180 * A316703 A362741 A192399
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 13 2006
STATUS
approved