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A006555 Minimal absolute value of discriminants of number fields of degree n with exactly 2 (1 pair of) complex embeddings.
(Formerly M3103)
1
3, 23, 275, 4511, 92779, 2306599 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
The old definition was "Minimal discriminant of number field of degree n."
From Jianing Song, Apr 29 2021: (Start)
Minimal absolute value of discriminants of number fields with signature r_1 = n - 2, r_2 = 1. For a number field F with degree n, the signature of F is a pair of numbers (r_1, r_2), where r_1 is the number of real embeddings of F, r_2 is half the number of complex embeddings of F. Obviously, we have r_1 + 2*r_2 = n.
This is the second column of A343290, negated. (End)
REFERENCES
H. Hasse, Number Theory, Springer-Verlag, NY, 1980, p. 617.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
EXAMPLE
From Jianing Song, Apr 29 2021: (Start)
The number field F of degree n with exactly 2 complex embeddings (signature r_1 = n - 2, r_2 = 1) whose discriminant is of minimal absolute value:
n = 2, F = Q[x]/(x^2 - x + 1), d = -3;
n = 3, F = Q[x]/(x^3 - x^2 + 1), d = -23;
n = 4, F = Q[x]/(x^4 - x^3 + 2x - 1), d = -275;
n = 5, F = Q[x]/(x^5 - x^3 - 2x^2 + 1), d = -4511;
n = 6, F = Q[x]/(x^6 - x^5 - 2x^4 + 3x^3 - x^2 - 2x + 1), d = -92779;
n = 7, F = Q[x]/(x^7 - 3x^5 - x^4 + x^3 + 3x^2 + x - 1), d = -2306599. (End)
CROSSREFS
Sequence in context: A199544 A302117 A343772 * A357349 A363137 A060090
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
Definition clarified by Jianing Song, Apr 29 2021
STATUS
approved

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Last modified April 16 08:27 EDT 2024. Contains 371698 sequences. (Running on oeis4.)