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A309139 Primes of the form 3*x^2 + 2*x*y + 8*y^2. 1
3, 13, 41, 71, 127, 139, 179, 257, 269, 311, 331, 409, 439, 443, 461, 541, 587, 673, 739, 761, 823, 887, 967, 1051, 1061, 1087, 1129, 1153, 1223, 1237, 1277, 1373, 1381, 1409, 1427, 1439, 1567, 1619, 1733, 1741, 1783, 1933, 1973, 2017, 2063, 2083, 2203, 2239, 2417 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in A028960.

Discriminant of positive definite binary quadratic form: -92.

LINKS

Table of n, a(n) for n=1..49.

Peter Luschny, Binary Quadratic Forms

N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

CROSSREFS

Cf. A028960. Subsequence of A106866.

Sequence in context: A289654 A095109 A259764 * A049167 A241527 A234387

Adjacent sequences:  A309136 A309137 A309138 * A309140 A309141 A309142

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Jul 14 2019

STATUS

approved

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Last modified June 18 11:58 EDT 2021. Contains 345098 sequences. (Running on oeis4.)