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A191952 Number of simple mixed arrangements of n pseudolines and 2 double pseudolines in the projective plane. 0
1, 4, 48, 1329, 80253 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..4.

J. Ferté, V. Pilaud and M. Pocchiola, On the number of simple arrangements of five double pseudolines, arXiv:1009.1575 [cs.CG], 2010; Discrete Comput. Geom. 45 (2011), 279-302.

CROSSREFS

Sequence in context: A211049 A321076 A166231 * A013145 A013150 A011266

Adjacent sequences:  A191949 A191950 A191951 * A191953 A191954 A191955

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Jun 20 2011

STATUS

approved

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Last modified December 8 01:54 EST 2019. Contains 329850 sequences. (Running on oeis4.)