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A121177 Catapolyoctagons (see Cyvin et al. for precise definition). 0
0, 2, 12, 62, 312 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

S. J. Cyvin et al., Enumeration of tree-like octagonal systems: catapolyoctagons, ACH Models in Chem. 134 (1997), 55-70.

LINKS

Table of n, a(n) for n=1..5.

P. E. Weidmann, The OEIS Sequencer survey, Apr 11 2015

FORMULA

a(n)=(5^n-5)/10. - Conjectured by Philipp Emanuel Weidmann, cf. link.

CROSSREFS

Sequence in context: A245091 A037562 A187001 * A125831 A226506 A026076

Adjacent sequences:  A121174 A121175 A121176 * A121178 A121179 A121180

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Aug 15 2006

STATUS

approved

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Last modified June 25 00:41 EDT 2017. Contains 288708 sequences.