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A045909 Number of unsymmetrical catafusenes with n hexagons (see reference for precise definition). 2
0, 0, 1, 8, 39, 190, 861, 3943, 17867, 81496, 372378, 1709842, 7879360, 36454004, 169239651, 788311290, 3683018475, 17255646688, 81056033636, 381668479192, 1801188588566, 8517994717214, 40360814900566, 191589547228523, 911009396044132, 4338777661726040 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Column C_s of Table 6 in Cyvin et al. Computed by subtracting all the other symmetry classes from the total. - Sean A. Irvine, Mar 27 2021

LINKS

Table of n, a(n) for n=0..25.

S. J. Cyvin, B. N. Cyvin, J. Brunvoll and E. Brendsdal, Enumeration and Classification of Certain Polygonal Systems Representing Polycyclic Conjugated Hydrocarbons: Annelated Catafusenes, Journal of Chemical Information and Modeling [formerly, J. Chem. Inform. Comput. Sci.], 34 (1994), pp. 1174-1180.

FORMULA

a(n) = A045906(n) - A045907(n) - A045908(n/2) - A342554(n/2) - A342570(n/2) - 2*A030529(n/4) - A055879(n/4) - [n=0] with sequences assumed to be 0 for non-integer arguments. - Sean A. Irvine, Mar 27 2021

CROSSREFS

Cf. A045906, A045907, A045908, A342554, A342570, A030529, A055879.

Sequence in context: A097787 A215731 A144414 * A264091 A319362 A154425

Adjacent sequences:  A045906 A045907 A045908 * A045910 A045911 A045912

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Sean A. Irvine, Mar 27 2021

STATUS

approved

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Last modified December 8 05:35 EST 2021. Contains 349590 sequences. (Running on oeis4.)