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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
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
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 A364151 A196568
KEYWORD
nonn
AUTHOR
Valery A. Liskovets, Mar 22 2005
STATUS
approved