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%I #26 May 28 2019 03:21:23
%S 0,0,2,5,26,101,457,1978,8851,39481,178043
%N Number of nonisomorphic systems of catafusenes in an example in Cyvin et al. (1994) with two appendages to the core indexed by the total number of hexagons in the appendages.
%C From _Petros Hadjicostas_, May 25 2019: (Start)
%C This is column alpha = 2 in Table 5 on p. 1179 of Cyvin et al. (1994). (The table starts with column alpha = 0.) Here, the index alpha for the columns in Table 5 is the number of appendages to the core.
%C The table refers to the example described on pp. 1177-1179 of the paper and especially to Figure 5 (p. 1178). The entries refer to the number of nonisomorphic systems of catafusenes in this example (as shown in Figure 5, p. 1178).
%C The rows of Table 5 are indexed by the total number of hexagons in the appendages.
%C Therefore, a(n) = number of nonisomorphic systems of catefusenes in the example on pp. 1177-1179 of Cyvin et al. (1994) with alpha = 2 appendages to the core, where n = total number of hexagons in the appendages.
%C From Note 10 (p. 1180) in Cyvin et al. (1994), we see that (most probably) the number of hexagons a (= n in this sequence) does not include any hexagons in the core.
%C (End)
%H S. J. Cyvin, B. N. Cyvin, J. Brunvoll and E. Brendsdal, <a href="https://doi.org/10.1021/ci00021a026">Enumeration and Classification of Certain Polygonal Systems Representing Polycyclic Conjugated Hydrocarbons: Annelated Catafusenes</a>, Journal of Chemical Information and Modeling [formerly, J. Chem. Inform. Comput. Sci.], 34 (1994), pp. 1174-1180.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Fusene.html">Fusene</a>.
%Y Cf. A121178.
%K nonn,more
%O 0,3
%A _N. J. A. Sloane_
%E Name edited by _Petros Hadjicostas_, May 25 2019
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