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A121140
Numbers of isomers of unbranched a-4-catapolyheptagons - see Brunvoll reference for precise definition.
0
1, 3, 21, 116, 692, 3776, 20216, 104448
OFFSET
3,2
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: A080952 A183404 A309670 * A005057 A092634 A178537
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 13 2006
STATUS
approved