A283659 Class numbers of the fields Q(sqrt(A283658(n))).

2, 3, 4, 8, 12, 14, 16, 20, 22, 28, 44, 48, 52, 58, 74, 96, 116, 130, 153, 154, 176, 180, 200, 230, 240, 256, 288, 296, 312, 316, 357, 394, 412, 452, 504, 540, 574, 575, 584, 616, 692, 924, 994, 1061, 1068, 1080, 1245, 1248, 1302, 1336

Offset

1,1

References

Z. I. Borevich and I. R. Shafarevich, Number Theory. Academic Press, NY, 1966.

Links

Table of n, a(n) for n=1..50.

Example

The sequence starts with 2 because the first number in A283658 is 10 and the class number of Q(sqrt(10)) equals 2.
The fifth term is 12 because A283658(5) = 226 and the class number of Q(sqrt(226)) is 12.

Mathematica

H = {}; hx = 1; d = 2; While[hx < 5, d++;
If[SquareFreeQ[d], h = NumberFieldClassNumber[Sqrt[d]];
  If[h > hx, AppendTo[H, h]; hx = h]]]; H

Crossrefs

Cf. A283658, A003649, A003172.

Sequence in context: A064418 A171164 A361108 * A355441 A344301 A032939

Adjacent sequences: A283656 A283657 A283658 * A283660 A283661 A283662

Keyword

nonn,more,changed

Author

Emmanuel Vantieghem, Mar 13 2017

Extensions

a(30)-a(50) from Robin Visser, May 25 2024

Status

approved