

A124157


Maximal number of edges in a doubly linear graph with n nodes.


1




OFFSET

1,3


COMMENTS

a(9) is known to be 34 or 35. I have put 35 here so as to distinguish this sequence from the triangular numbers. But the true value is (or was in 1997 at least) not known.


REFERENCES

L. W. Beineke, Biplanar graphs: a survey, Computers Math. Applic., 34 (1997), 18.
Hutchinson, Joan P.; Shermer, Thomas; and Vince, Andrew; On representations of some thicknesstwo graphs. Comput. Geom. 13 (1999), 161171.


LINKS

Table of n, a(n) for n=1..9.


FORMULA

For n >= 10, 6n20 <= a(n) <= 6n18.


CROSSREFS

Sequence in context: A124158 A161208 A109444 * A033440 A067525 A130487
Adjacent sequences: A124154 A124155 A124156 * A124158 A124159 A124160


KEYWORD

nonn,more


AUTHOR

N. J. A. Sloane, Dec 02 2006


STATUS

approved



