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A120991 Number of free hexagonal polygons of symmetry class C_(2v) and area n. 3
0, 0, 1, 1, 9, 12, 39, 61, 178, 274, 796, 1251, 3578, 5692, 16290, 26069, 74980, 120676, 348564, 563503, 1635175, 2652445, 7729807, 12574028, 36784467, 59975232, 176063801, 287613473, 846967739, 1385815492, 4092516853, 6705360813, 19852731854, 32565589836, 96642900684 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,5
LINKS
Markus Vöge, Anthony J. Guttmann and Iwan Jensen, On the number of benzenoid hydrocarbons, J. Chem. Inf. Comput. Sci., (2002), vol. 42, 456-466. See Table 3 under the column C_(2c) [sic. This is a typo, should be C_(2v) instead].
CROSSREFS
Sequence in context: A216297 A024312 A024877 * A253088 A341208 A328120
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Aug 19 2006
EXTENSIONS
More terms from N. J. A. Sloane, Aug 27 2006
Name corrected by Andrey Zabolotskiy, Nov 10 2023
STATUS
approved

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Last modified June 5 20:25 EDT 2024. Contains 373110 sequences. (Running on oeis4.)