A128041 Triangle read by columns: number of n-node (unlabeled) graphs with girth k, for n >= 3, k >= 3.

1, 4, 1, 20, 3, 1, 118, 15, 2, 1, 937, 59, 8, 2, 1, 11936, 296, 26, 9, 2, 1, 272771, 1604, 101, 28, 8, 2, 1, 11992996, 11303, 396, 107, 25, 9, 2, 1, 1018892793, 102108, 1744, 376, 92, 29, 9, 2, 1, 165089910412, 1250114, 8531, 1457, 321, 113, 30, 10, 2, 1

Offset

3,2

Links

Table of n, a(n) for n=3..57.

Example

Number of n-node (unlabeled) graphs with girth k, for n >= 3, k >= 3.
.k..|.n=........3........4........5........6........7........8........9........10
---------------------------------------------------------------------------------
.0..|...........0........0........0........0........0........0........0.........0
.1..|...........0........0........0........0........0........0........0.........0
.2..|...........0........0........0........0........0........0........0.........0
.3..|...........1........4.......20......118......937....11936...272771..11992996
.4..|...........0........1........3.......15.......59......296.....1604.....11303
.5..|...........0........0........1........2........8.......26......101.......396
.6..|...........0........0........0........1........2........9.......28.......107
.7..|...........0........0........0........0........1........2........8........25
.8..|...........0........0........0........0........0........1........2.........9
.9..|...........0........0........0........0........0........0........1.........2
10..|...........0........0........0........0........0........0........0.........1

Prog

(nauty) geng $n | countg --ng # Martin Fuller, May 03 2015

Crossrefs

Cf. A128042, A006787, A128236-A128243.

Sequence in context: A349708 A249716 A333273 * A144885 A144886 A117380

Adjacent sequences: A128038 A128039 A128040 * A128042 A128043 A128044

Keyword

nonn,tabl

Author

Keith Briggs, May 05 2007

Extensions

Corrected and extended by Martin Fuller, May 01 2015

Status

approved