A238370 Number of rational curves on S of degree d passing through d-1 general points, where S is a general cubic surface in projective 3-space.

27, 27, 72, 216, 459, 936

Offset

1,1

Comments

Finding a recursive formula (à la Kontsevich for A013587?) remains open.

The famous 27 lines on a cubic surface is the case a(1) = 27. - Michael Somos, Feb 25 2014

Links

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

Steven R. Finch, Enumerative geometry, February 24, 2014. [Cached copy, with permission of the author]

W. Traves, Conics on the cubic surface, MAAC 2004, George Mason University.

Crossrefs

Cf. A013587, A027363.

Sequence in context: A164862 A040703 A022361 * A056131 A253102 A165848

Adjacent sequences: A238367 A238368 A238369 * A238371 A238372 A238373

Keyword

nonn,more

Author

Steven Finch, Feb 25 2014

Status

approved