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A121115 Related to enumeration of rooted catapolyoctagons (see Cyvin reference for precise definition). 3
0, 1, 10, 87, 742, 6355, 54972, 480676, 4246156, 37857609, 340321820, 3081805727, 28089617550, 257516093302, 2373098818888, 21971084873775, 204274300836144, 1906474633391853, 17854760020687254, 167745930396293263, 1580556744351118030, 14932307414985485049, 141420575129236412394 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

S. J. Cyvin, B. N. Cyvin, and J. Brunvoll. Enumeration of tree-like octagonal systems: catapolyoctagons, ACH Models in Chem. 134 (1997), 55-70, Table III, W_r.

LINKS

Table of n, a(n) for n=1..23.

FORMULA

a(n) = Sum_{i=1..n-1} A036758(i)*A036758(n-i) [Cyvin eq. (18)]. - R. J. Mathar, Jul 31 2019

CROSSREFS

Sequence in context: A251193 A198858 A331793 * A292998 A114648 A217417

Adjacent sequences:  A121112 A121113 A121114 * A121116 A121117 A121118

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Aug 13, 2006

STATUS

approved

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Last modified January 26 16:58 EST 2020. Contains 331280 sequences. (Running on oeis4.)