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A133315 Positive discriminants with form class number 1. 0
5, 8, 12, 13, 17, 20, 21, 24, 28, 29, 32, 33, 37, 41, 44, 45, 48, 52, 53, 56, 57, 61, 68, 69, 72, 73, 76, 77, 80, 84, 88, 89, 92, 93, 97, 101, 108, 109, 112, 113, 116, 117, 124, 125, 128, 129, 132, 133, 137, 141, 149, 152, 153, 157, 161, 164, 172, 173, 176, 177, 180, 181, 184, 188, 189, 193, 197, 201, 208 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

D. A. Cox, Primes of the form x^2+ny^2, Wiley, New York, 1989.

D. E. Flath, Introduction to Number Theory, Wiley-Interscience, 1989.

LINKS

Table of n, a(n) for n=1..69.

PROG

(PARI) isA133315 (n) = (n % 4 <= 1) && (! issquare(n)) && (qfbclassno(n, 1) == 1) \\ Michel Marcus, May 23 2013

CROSSREFS

Sequence in context: A294227 A116602 A079896 * A003658 A003656 A003246

Adjacent sequences:  A133312 A133313 A133314 * A133316 A133317 A133318

KEYWORD

nonn

AUTHOR

David Brink, Dec 30 2007

STATUS

approved

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Last modified April 16 05:20 EDT 2021. Contains 343030 sequences. (Running on oeis4.)