Discussion and Depiction of Forms

It is a fact that the algorithm (Par. 3.5.3) does not generate all the p-tuple coronoids with h = This is easily demonstrated by examples. 

For = 3 it is inferred from Table 3 jjjjj (3) = 13 + 5 = 18. In addition to the smallest triple coronoid (with h = 18) derived from phenalene according to the algorithm one 

Notice that this derivation does not follow the algorithm because anthracene (ChHio) is not an extremal benzenoid. It has as its number of vertices = 14 which equals 13 (cf. 

Pj in( ) by definition always pertains to an extremal benzenoid. It follows that, for anthracene, 

In the second example of Par. 3.5.3 the unique smallest multiple coronoid for = 7 was derived from coronene according to the algorithm under consideration. Another such system emerges from C25H13 benzo[/u]anthanthrene. This nonextremal benzenoid has 25 internal vertices (iV) against = 24 (cf. Table 3). On the other hand, its minimum number of parallel 

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