A323930
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
1, 1, 3, 7, 22, 81, 331, 1436, 6510, 30129, 141512, 671538, 3210620, 15443871, 74662005, 362506902
Offset: 1
- N. Trinajstić, S. Nikolić, J. V. Knop, W. R. Müller and K. Szymanski, Computational Chemical Graph Theory: Characterization, Enumeration, and Generation of Chemical Structures by Computer Methods, Ellis Horwood, 1991. [incorrectly gives a(12) = 671512 in Table 4.13]
- Björg N. Cyvin, Jon Brunvoll and Sven J. Cyvin, Enumeration of benzenoid systems and other polyhexes, p. 65-180 in: I. Gutman (ed.), Advances in the Theory of Benzenoid Hydrocarbons II, Springer, 1992.
- Wenchen He and Wenjie He, Generation and enumeration of planar polycyclic aromatic hydrocarbons, Tetrahedron 42.19 (1986): 5291-5299. See Table 1.
- Lorentz Jäntschi, Topological Characterization of a Complete Set of Small‐Sized Graphene Sheets Using Molecular Descriptors With Energy Storage Applications, Ener. Stor. (2025) Vol. 7, Issue 6, Art No. e70253.
A018190 is a very similar sequence with (as He and He remark) a slightly different definition. Cf.
A000228,
A038147.
a(10)-a(16) from Cyvin, Brunvoll & Cyvin (Table 1) added by
Andrey Zabolotskiy, Feb 08 2023
A323924
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
0, 0, 0, 1, 3, 6, 22, 58
Offset: 1
A323929
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
0, 0, 1, 1, 7, 30, 141, 671, 3284, 15998, 78505, 385766, 2214783, 9382168
Offset: 1
- N. Trinajstić, S. Nikolić, J. V. Knop, W. R. Müller and K. Szymanski, Computational Chemical Graph Theory: Characterization, Enumeration, and Generation of Chemical Structures by Computer Methods, Ellis Horwood, 1991.
a(10)-a(14) from Trinajstić et al. (Table 4.11, the number of non-Kekuléan polyhexes with h hexagons) added by
Andrey Zabolotskiy, Feb 08 2023
A323925
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
0, 0, 0, 0, 2, 12, 66, 331, 1678
Offset: 1
A323926
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
1, 1, 2, 6, 15, 51, 190, 765, 3226, 14131, 63007, 285772, 995837, 6061703
Offset: 1
- N. Trinajstić, S. Nikolić, J. V. Knop, W. R. Müller and K. Szymanski, Computational Chemical Graph Theory: Characterization, Enumeration, and Generation of Chemical Structures by Computer Methods, Ellis Horwood, 1991.
a(10)-a(14) from Trinajstić et al. (Table 4.6, the number of Kekuléan polyhexes with h hexagons) added by
Andrey Zabolotskiy, Feb 08 2023
A323927
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
0, 0, 1, 0, 1, 3, 9, 27, 119
Offset: 1
A323928
Polycyclic aromatic hydrocarbons (for precise definition see He and He, 1986).
Original entry on oeis.org
0, 0, 0, 1, 6, 27, 132, 644, 3165
Offset: 1
Showing 1-7 of 7 results.