A110887 Number of configurations of n skew lines up to isotopy.

1, 1, 2, 3, 7, 19, 74

Offset

1,3

References

A. Borobia and V. F. Mazurovskii, On diagrams of configurations of 7 skew lines in R^3, Amer. Math. Soc. Transl. (2) 173 (1996), 33-40

A. Borobia and V. F. Mazurovskii, Nonsingular configurations of 7 lines in RP^3, J. Knot Theory Ramif. 6(6) (1997), 751-783

O. Y. Viro and Y. V. Drobotukhina, Configurations of skew lines, Leningrad Math. J. 1(4) (1990), 1027-1050

Links

Table of n, a(n) for n=1..7.

Crossrefs

Sequence in context: A025563 A336296 A224929 * A065060 A164625 A294148

Adjacent sequences: A110884 A110885 A110886 * A110888 A110889 A110890

Keyword

hard,more,nonn

Author

David Garber, Sep 20 2005

Status

approved