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A121178 Four-column table read by rows: number of nonisomorphic systems of catafusenes in an example (see Cyvin et al. (1994) for precise definition). 5
1, 0, 0, 0, 2, 2, 0, 0, 6, 5, 1, 0, 19, 26, 5, 1, 71, 101, 31, 2, 274, 457, 160, 16, 1117, 1978, 825, 80, 4650, 8851, 4074, 473, 19819, 39481, 19902, 2517, 85710, 178043, 95920, 13431 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

From Petros Hadjicostas, May 25 2019: (Start)

The sequence (a rectangular array) refers to Table 5 on p. 1179 of Cyvin et al. (1994). The zeroth row and the zeroth column from Table 5 do not appear in this sequence. The columns (alpha = 1, 2, 3, 4) refer to the number of appendages to the core.

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).

The rows of the table are indexed by the total number of hexagons in the appendages.

(End)

LINKS

Table of n, a(n) for n=1..40.

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.

Eric Weisstein's World of Mathematics, Fusene.

EXAMPLE

The table begins:

     1,    0,    0,   0;

     2,    2,    0,   0;

     6,    5,    1,   0;

    19,   26,    5,   1;

    71,  101,   31,   2;

   274,  457,  160,  16;

  1117, 1978,  825,  80;

  4650, 8851, 4074, 473;

  ...

CROSSREFS

Columns give A044045, A045903 - A045905. Row sums give A045906.

Sequence in context: A298070 A298719 A296148 * A175917 A320525 A069971

Adjacent sequences:  A121175 A121176 A121177 * A121179 A121180 A121181

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, Aug 15 2006; corrected Apr 14 2013. Thanks to Michel Marcus for noticing that something was wrong.

EXTENSIONS

Name edited by Petros Hadjicostas, May 25 2019

More terms from reference from Petros Hadjicostas, May 25 2019

STATUS

approved

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Last modified October 25 13:27 EDT 2021. Contains 348252 sequences. (Running on oeis4.)