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A367669
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Number of degree 3 number fields unramified outside the first n prime numbers.
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2
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OFFSET
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1,2
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COMMENTS
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B. Matschke showed that a(11) = 340618 assuming the Generalized Riemann Hypothesis.
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LINKS
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EXAMPLE
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For n = 1, there are no cubic number fields unramified away from 2, so a(1) = 0.
For n = 2, the a(2) = 9 cubic number fields unramified away from {2,3} can be given by Q(a) where a is a root of x^3 - 3x - 1, x^3 - 2, x^3 + 3x - 2, x^3 - 3, x^3 - 3x - 4, x^3 - 3x - 10, x^3 - 12, x^3 - 6, or x^3 - 9x - 6.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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