A003651 Class number of real quadratic field with discriminant 4n, n == 2,3 ( mod 4). (Formerly M0066)

1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 2, 1, 2, 1, 2, 2, 3, 4, 1, 1, 2, 2, 1, 2, 2, 1, 2, 1, 2, 2, 2, 2, 1, 2, 2, 2, 1, 4, 1, 1, 2, 1, 3, 2, 2, 1, 2, 2, 1, 2, 1, 1, 1, 4, 2, 2, 1, 2, 2, 2, 2, 2, 1, 2, 4, 1, 2, 2, 1, 4, 1, 1, 2, 2, 4, 2, 3, 8, 1, 2, 4, 6, 2, 1, 2, 2, 1, 3

Offset

2,5

References

D. A. Buell, Binary Quadratic Forms. Springer-Verlag, NY, 1989, pp. 224-241.

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.

Crossrefs

Cf. A003650.

Sequence in context: A120675 A072699 A143589 * A325028 A073203 A073204

Adjacent sequences: A003648 A003649 A003650 * A003652 A003653 A003654

Keyword

nonn

Author

N. J. A. Sloane, Mira Bernstein

Status

approved