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A094614 Fundamental discriminants of real quadratic number fields with class number 5. 11
401, 817, 1093, 1393, 1429, 1641, 1756, 1897, 1996, 2081, 2153, 2908, 3121, 3181, 3253, 3928, 3997, 4353, 4357, 4441, 4504, 4757, 4889, 5241, 5269, 5308, 5944, 6113, 6157, 6481, 6949, 7064, 7229, 7513, 7817, 7861, 8049, 8108, 8121, 8309, 8501, 8689, 9181, 9229 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Class Number
MATHEMATICA
Select[Range[9229], NumberFieldDiscriminant@Sqrt[#] == # && NumberFieldClassNumber@Sqrt[#] == 5 &] (* Arkadiusz Wesolowski, Oct 22 2012 *)
PROG
(PARI) {ok(n) = n>10 && isfundamental(n) && qfbclassno(n)==5};
for(n=1, 10000, if(ok(n)==1, print1(n, ", "))) \\ G. C. Greubel, Mar 01 2019
(Sage)
is_fund_and_qfbcn_1 = lambda n: is_fundamental_discriminant(n) and QuadraticField(n, 'a').class_number() == 5;
A094614 = lambda n: filter(is_fund_and_qfbcn_1, (1, 2, .., n));
A094614(10000) # G. C. Greubel, Mar 01 2019
CROSSREFS
Sequence in context: A332674 A141026 A158313 * A104926 A031718 A102324
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, May 14 2004
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)