A104888 Class number of binary quadratic forms with radicand A005117(n).

1, 2, 1, 2, 2, 2, 2, 1, 2, 4, 1, 2, 2, 2, 2, 2, 1, 4, 2, 2, 4, 4, 1, 2, 4, 1, 4, 2, 2, 2, 4, 1, 4, 2, 2, 2, 1, 2, 2, 4, 2, 2, 4, 2, 1, 2, 2, 4, 6, 4, 2, 2, 2, 4, 1, 4, 2, 2, 4, 1

Offset: 2

Author

Steven Finch, May 03 2005

Keywords

• nonn

Comments

The fundamental discriminant D and the radicand m (which is squarefree) are related via D=m if m=1 (mod 4) and D=4*m if m=2,3 (mod 4).

References

• Hua Loo Keng, Introduction to Number Theory, Springer-Verlag, 1982, pp. 465-472.

Links

• S. R. Finch, Class number theory
• Steven R. Finch, Class number theory [Cached copy, with permission of the author]
• Jens Jonasson, Classes of integral binary quadratic forms, Master's thesis (2001), Appendix B.

Crossrefs

Cf. A003646, A087048.