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A104591 Number of labeled non-planar non-projective-planar toroidal 2-connected K_{3,3}-subdivision-free graphs with no vertex of degree 2 and with n vertices. 1
560, 5040, 957600, 123354000, 16842764400, 2764379217600, 527554510282800, 114387072405606000, 27728561968887780000, 7418031804967840056000, 2167306256125914230527200, 685709965521372865035362400, 233306923207078035272369412000 (list; graph; refs; listen; history; text; internal format)
OFFSET

8,1

COMMENTS

By empirical evidence, the terms possess a curious prime factor behavior. E.g. 2^5*3^3*5^3*7^2*11*13*17*19 divides a(20)=233306923207078035272369412000.

LINKS

Table of n, a(n) for n=8..20.

A. Gagarin, G. Labelle and P. Leroux, Characterization and enumeration of toroidal K_{3,3}-subdivision-free graphs, arXiv:math/0411356 [math.CO], 2004.

CROSSREFS

Cf. A104590.

Sequence in context: A249839 A069243 A169719 * A318119 A196568 A171347

Adjacent sequences:  A104588 A104589 A104590 * A104592 A104593 A104594

KEYWORD

nonn

AUTHOR

Valery A. Liskovets, Mar 22 2005

STATUS

approved

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Last modified December 3 05:29 EST 2020. Contains 338899 sequences. (Running on oeis4.)