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A283659 Class numbers of the fields Q(sqrt(A283658(n))). 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
REFERENCES
Z. I. Borevich and I. R. Shafarevich, Number Theory. Academic Press, NY, 1966.
LINKS
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
Sequence in context: A064418 A171164 A361108 * A355441 A344301 A032939
KEYWORD
nonn,more
AUTHOR
Emmanuel Vantieghem, Mar 13 2017
STATUS
approved

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Last modified April 25 05:56 EDT 2024. Contains 371964 sequences. (Running on oeis4.)