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%I #18 Mar 15 2018 04:44:10
%S 0,2,8,9,11,17,18,27,32,36,38,41,44,50,54,59,68,72,81,83,86,89,98,99,
%T 107,108,113,128,131,134,137,144,146,152,153,162,164,171,176,179,194,
%U 198,200,209,216,225,227,233,236,242,243,251,257,272,275,278,281,288,297,306,323
%N Numbers of form 2 x^2 + 9 y^2.
%H Harvey P. Dale, <a href="/A020676/b020676.txt">Table of n, a(n) for n = 1..1000</a>
%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 = 350}, Select[Union[2#[[1]]^2 + 9#[[2]]^2&/@Tuples[Range[0, Ceiling[Sqrt[upto^2/2]]], 2]], # <= upto &]] (* _Harvey P. Dale_, May 30 2017 *)
%Y Subsequences include A001105, A016766.
%Y Cf. A106949 (prime terms).
%K easy,nonn
%O 1,2
%A _David W. Wilson_