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A072904 Nonsquares m such that the discriminant of the quadratic field Q(sqrt(m)) < m. 2
18, 20, 27, 32, 45, 48, 50, 52, 54, 63, 68, 72, 75, 80, 84, 90, 96, 98, 99, 108, 112, 116, 117, 125, 126, 128, 132, 135, 147, 148, 150, 153, 160, 162, 164, 171, 175, 176, 180, 189, 192, 198, 200, 207, 208, 212, 216, 224, 228, 234, 240, 242, 243, 244, 245, 250 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) appears to be asymptotic to C*n with C = 3.4... .
MATHEMATICA
Select[Range[250], !IntegerQ@Sqrt[#] && NumberFieldDiscriminant[Sqrt[#]] < # &] (* Amiram Eldar, Jun 24 2022 *)
PROG
(PARI) isok(m) = !issquare(m) && (quaddisc(m) < m); \\ Michel Marcus, Feb 18 2021
CROSSREFS
Cf. A037449.
Intersection of A000037 and A072903.
Sequence in context: A295745 A328934 A255848 * A268284 A367268 A054279
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Aug 10 2002
STATUS
approved

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Last modified March 1 16:12 EST 2024. Contains 370442 sequences. (Running on oeis4.)