A120371 Number of isomers of polyhex hydrocarbons with C_(2h) symmetry with eighteen hexagons.

1, 14, 59, 206, 601, 1602, 3832, 8050, 14601, 22472, 24071, 14756

Offset

52,2

Comments

See Table 3 column 3 on page 614 of the paper by Caporossi and Hansen. Also the sequence starts for the hydrocarbon C_52H_18. If the number of carbons is an odd number then the number of isomers with this symmetry is zero.

References

G. Caporossi and P. Hansen, "Enumeration of Polyhex Hydrocarbons to h=21", J. Chem. Inf. Comput. Sci., vol. 38 (1998) pp. 610-619.

Links

Table of n, a(n) for n=52..63.

Example

If the number of carbons is 54 then the number of isomers of polyhex hydrocarbons with C_(2h) symmetry with eighteen hexagons is 14 which is the third term in the sequence.

Crossrefs

Cf. A018190.

Sequence in context: A033856 A143861 A100174 * A062022 A277986 A261282

Adjacent sequences: A120368 A120369 A120370 * A120372 A120373 A120374

Keyword

nonn

Author

Parthasarathy Nambi, Aug 27 2006

Status

approved