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A191951 Number of simple mixed arrangements of n pseudolines and 1 double pseudoline in the projective plane. 0
1, 1, 2, 5, 25, 302, 9194, 556298 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..7.

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: A191506 A139007 A015486 * A120767 A051771 A008318

Adjacent sequences:  A191948 A191949 A191950 * A191952 A191953 A191954

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Jun 20 2011

STATUS

approved

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Last modified December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)