A335820 Number of squarefree graphs on n nodes with maximal number of edges.

1, 1, 1, 1, 1, 4, 5, 5, 10, 2, 11, 3, 2, 1, 2, 2, 1, 1, 5, 1, 1, 13, 1, 20, 9, 8, 7, 1, 2, 1, 1, 9, 18, 1, 1, 5, 11

Offset: 1

Author

Jason Zimba, Jul 22 2020

Keywords

• nonn
• more

Comments

Number of squarefree graphs on n nodes with A006855(n) edges.

Examples

			There are 2 squarefree graphs on 10 nodes that have maximal number of edges.
		

Links

• C. R. J. Clapham, A. Flockhart, and J. Sheehan, Graphs without Four-Cycles, Journal of Graph Theory, 31 (1989), 29-47.
• D. B. West, A. Bialostocki, and J. Schonheim, E3387 (Large Graphs with No 4-cycle), The American Mathematical Monthly, 98 (Aug. - Sep. 1991), 653-655.

Crossrefs

Unlabeled version of A191966.

Cf. A006786, A006855, A077269, A300756.

Extensions

a(22)-a(37) from Brendan McKay, Mar 08 2022