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A049336 Triangle T(n,k) = number of 2-connected planar graphs with n >= 1 nodes and 0<=k<=3n-6 edges. 3
0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 2, 3, 2, 1, 0, 0, 0, 0, 0, 0, 1, 3, 9, 13, 11, 5, 2, 0, 0, 0, 0, 0, 0, 0, 1, 4, 20, 49, 77, 75, 47, 16, 5, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 40, 158, 406, 662, 737, 538, 259, 72, 14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 7, 70, 426, 1645, 4176 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,21

REFERENCES

A. Gagarin, G. Labelle, P. Leroux and T. Walsh, Structure and enumeration of two-connected graphs with prescribed three-connected components,  Adv. in Appl. Math. 43 (2009), no. 1, 46-74.

LINKS

Ruperto Corso, Table of n, a(n) for n = 1..249

A. Gagarin, G. Labelle, P. Leroux, and T. Walsh, Structure and enumeration of two-connected graphs with prescribed three-connected components, Adv. in Appl. Math. 43 (2009), no. 1, pp. 46-74.

EXAMPLE

0; 0,0; 0,0,0,1; 0,0,0,0,1,1,1; 0,0,0,0,0,1,2,3,2,1; 0,0,0,0,0,0,1,3,9...

CROSSREFS

Cf. A021103, A003094, A049334.

Sequence in context: A152954 A079175 A202815 * A017888 A017878 A301572

Adjacent sequences:  A049333 A049334 A049335 * A049337 A049338 A049339

KEYWORD

nonn,tabf,easy,nice

AUTHOR

Brendan McKay

EXTENSIONS

More terms, a(86) onwards, from Gilbert Labelle (labelle.gilbert(AT)uqam.ca), Jan 20 2009

STATUS

approved

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Last modified February 17 18:14 EST 2020. Contains 332005 sequences. (Running on oeis4.)