A003646 - OEIS

A003646

Class number of binary quadratic forms with fundamental discriminant A003658(n),n>=2.
(Formerly M0077)

1, 1, 2, 1, 1, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 2, 2, 4, 1, 2, 2, 1, 2, 2, 2, 2, 1, 2, 2, 1, 1, 2, 4, 1, 1, 4, 2, 2, 2, 4, 1, 4, 2, 4, 1, 2, 4, 1, 2, 4, 4, 2, 1, 2, 1, 2, 2, 2, 1, 1, 2, 4, 4, 2, 2, 2, 4, 4, 3, 2, 1, 2, 2, 1, 2, 2, 2, 3, 4, 2, 2, 1, 4, 1, 4, 1, 2, 4, 1, 2, 2, 4, 2, 4, 1, 6, 1, 6, 4, 2, 2, 1, 2, 2, 4

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OFFSET

2,3

REFERENCES

D. A. Buell, Binary Quadratic Forms. Springer-Verlag, NY, 1989, pp. 236, 241.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=2..106.

S. R. Finch, Class number theory

Steven R. Finch, Class number theory [Cached copy, with permission of the author]

Wolfdieter Lang, Table for a(n), n=2, ..., 92 (see Part 2).

CROSSREFS