login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A283659 Class numbers of the fields Q(sqrt(A283658(n))). 1

%I #12 May 26 2024 17:58:46

%S 2,3,4,8,12,14,16,20,22,28,44,48,52,58,74,96,116,130,153,154,176,180,

%T 200,230,240,256,288,296,312,316,357,394,412,452,504,540,574,575,584,

%U 616,692,924,994,1061,1068,1080,1245,1248,1302,1336

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

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

%e The sequence starts with 2 because the first number in A283658 is 10 and the class number of Q(sqrt(10)) equals 2.

%e The fifth term is 12 because A283658(5) = 226 and the class number of Q(sqrt(226)) is 12.

%t H = {}; hx = 1; d = 2; While[hx < 5, d++;

%t If[SquareFreeQ[d], h = NumberFieldClassNumber[Sqrt[d]];

%t If[h > hx, AppendTo[H, h]; hx = h]]]; H

%Y Cf. A283658, A003649, A003172.

%K nonn,more

%O 1,1

%A _Emmanuel Vantieghem_, Mar 13 2017

%E a(30)-a(50) from _Robin Visser_, May 25 2024

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 31 11:17 EDT 2024. Contains 374780 sequences. (Running on oeis4.)