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A342570 Number of catafusenes with 2n hexagons and D_{2h}(a) symmetry. 2
0, 1, 1, 3, 4, 9, 13, 29, 46, 101, 167, 375, 644, 1461, 2563, 5899, 10534, 24469, 44237, 103643, 189302, 446381, 821905, 1948853, 3612868, 8605289, 16044151, 38362199, 71877226, 172423769, 324440379, 780496109, 1474118424, 3554991269, 6736507309, 16281079899 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
Column D_{2h}(a) in Table 6 and Eq. (51) in Cyvin et al.
LINKS
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) = A055879(n) + (1/2) * (A039658(n) - A055879(n/2)) where A055879 is 0 for non-integer arguments.
CROSSREFS
Sequence in context: A056514 A151517 A219043 * A050163 A207016 A333333
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Mar 27 2021
STATUS
approved

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Last modified June 13 17:32 EDT 2024. Contains 373391 sequences. (Running on oeis4.)