A027845 Number of subgroups of index n in fundamental group of a certain fiber space.

1, 15, 43, 371, 1321, 11979

Offset

1,2

References

V. A. Liskovets and A. Mednykh, Enumeration of subgroups in the fundamental groups of orientable circle bundles over surfaces, Commun. in Algebra, 28, No. 4 (2000), 1717-1738.

Links

Table of n, a(n) for n=1..6.

Crossrefs

Sequence in context: A126369 A193647 A133343 * A201810 A364081 A292018

Adjacent sequences: A027842 A027843 A027844 * A027846 A027847 A027848

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved