|
| |
|
|
A018231
|
|
Numbers n such that normalizer of Gamma_0(n) is a triangle group.
|
|
3
| |
|
|
1, 2, 3, 4, 8, 9, 12, 16, 18, 27, 32, 36, 48, 64, 72, 108, 128, 144, 1152, 192, 1728, 576, 288, 432
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
REFERENCES
| Akbas and Singerman, The signature of the normalizer..., in Graphs, Combinatorics and Geometry, ed. Liebeck and Saxl, LMSLNS 165, Cambridge Univ. Press, 1992, 77-86.
|
|
|
CROSSREFS
| Cf. A018229, A018228, A018230.
Sequence in context: A032859 A032883 A023786 * A085256 A127483 A130804
Adjacent sequences: A018228 A018229 A018230 * A018232 A018233 A018234
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
| |
|
|
