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A035115
Relative class number h- of cyclotomic field Q(zeta_m) where m is n-th term of A035113.
4
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 2, 1, 3, 2, 3, 1, 8, 9, 5, 17, 8, 5, 9, 4, 37, 9, 7, 19, 19, 121, 10, 11, 55, 55, 11, 211, 43, 69, 201, 695, 64, 351, 13, 468, 39, 507, 156, 84, 75, 4889, 2593, 1536, 10752, 41241, 76301, 1280, 6795
OFFSET
1,28
REFERENCES
L. C. Washington, Introduction to Cyclotomic Fields, Springer, p. 353.
FORMULA
a(n) = A061653(A035113(n)).
MATHEMATICA
(* This is only a recomputation of the existing data. *)
terms = 76;
A035113 = Sort[Select[Range[3 terms], Mod[#, 4] != 2&], EulerPhi[#1] <= EulerPhi[#2]&];
A061653 = Import["https://oeis.org/A061653/b061653.txt", "Table"][[All, 2]];
a[n_] := A061653[[A035113[[n]] ]];
Array[a, terms] (* Jean-François Alcover, Aug 17 2019 *)
CROSSREFS
KEYWORD
nonn,nice
EXTENSIONS
Changed 41421 to 41241, value is given incorrectly in first edition of Washington, Matthew Johnson, Jul 20 2013
STATUS
approved