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Numbers of form 3 x^2 + 5 y^2.
1

%I #15 May 22 2015 13:35:10

%S 0,3,5,8,12,17,20,23,27,32,45,47,48,53,57,68,72,75,80,83,92,93,95,107,

%T 108,113,120,125,128,137,147,152,153,155,167,173,180,183,188,192,197,

%U 200,207,212,227,228,233,237,243,245,248,255,257,263,272,288,293,300,305,317

%N Numbers of form 3 x^2 + 5 y^2.

%C Discriminant -60.

%H N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)

%t With[{upto=320},Select[Union[3#[[1]]^2+5#[[2]]^2&/@ Tuples[ Range[ 0, Ceiling[ Sqrt[upto]]],2]],#<+upto&]] (* _Harvey P. Dale_, May 22 2015 *)

%Y The primes in this sequence are given by A106859 (excluding 2). - _N. J. A. Sloane_, Jun 01 2014

%K easy,nonn

%O 1,2

%A _David W. Wilson_