A121212 - OEIS

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A121212

Number of free hexagonal polygons of symmetry class C_(3h) and area n.

0, 0, 0, 0, 0, 1, 1, 0, 5, 5, 0, 21, 26, 0, 95, 118, 0, 423, 543, 0, 1923, 2507, 0, 8869, 11676, 0, 41410, 54893, 0, 195353, 260220, 0, 929423, 1242820, 0 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,9`
	REFERENCES	`Markus Voege, 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 C_(3h) column.`
	LINKS	`Table of n, a(n) for n=1..35.`
	CROSSREFS	`Sequence in context: A233383 A144184 A119380 * A182787 A133337 A279932` `Adjacent sequences: A121209 A121210 A121211 * A121213 A121214 A121215`
	KEYWORD	`nonn`
	AUTHOR	`Parthasarathy Nambi, Aug 19 2006`
	STATUS	`approved`

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Last modified December 11 22:04 EST 2018. Contains 318052 sequences. (Running on oeis4.)