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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,28

REFERENCES

L. C. Washington, Introduction to Cyclotomic Fields, Springer, p. 353.

LINKS

Table of n, a(n) for n=1..76.

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-Fran├žois Alcover, Aug 17 2019 *)

CROSSREFS

Cf. A000010, A035113, A035114, A055513, A061494, A061653.

Sequence in context: A029351 A178638 A290496 * A146969 A090270 A326441

Adjacent sequences:  A035112 A035113 A035114 * A035116 A035117 A035118

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Changed 41421 to 41241, value is given incorrectly in first edition of Washington, Matthew Johnson, Jul 20 2013

STATUS

approved

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Last modified September 20 02:20 EDT 2019. Contains 327207 sequences. (Running on oeis4.)