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%I #25 Mar 27 2024 10:38:04
%S 14,30,46,56,62,78,94,110,120,126,142,158,174,184,190,206,222,224,238,
%T 248,254,270,286,302,312,318,334,350,366,376,382,398,414,430,440,446,
%U 462,478,480,494,504,510,526,542,558,568,574,590,606,622
%N Numbers of the form 2^(2i+1)*(8j+7).
%C The numbers not of the form x^2+y^2+2z^2.
%C These are the numbers not occurring as norms in the face-centered cubic lattice (cf. A004015).
%C Numbers whose base 4 representation ends in 3,2 followed by some number of zeros. - _Franklin T. Adams-Watters_, Dec 04 2006
%H T. D. Noe, <a href="/A055039/b055039.txt">Table of n, a(n) for n=1..10000</a>
%H L. E. Dickson, <a href="http://dx.doi.org/10.1090/S0002-9904-1927-04312-9">Integers represented by positive ternary quadratic forms</a>, Bull. Amer. Math. Soc. 33 (1927), 63-70.
%H L. J. Mordell, <a href="http://dx.doi.org/10.1093/qmath/os-1.1.276">A new Waring's problem with squares of linear forms</a>, Quart. J. Math., 1 (1930), 276-288 (see p. 283).
%H Steve Waterman, <a href="http://watermanpolyhedron.com/MISSING.html">Missing numbers formula</a>
%F Consists of numbers of the form 6x^2 + 8x^2*(2y -1). (Steve Waterman).
%e In base 4: 32, 132, 232, 320, 332, 1032, 1132, 1232, 1320, 1332, 2032,...
%o (Python)
%o from itertools import count, islice
%o def A055039_gen(startvalue=1): # generator of terms >= startvalue
%o return filter(lambda n:(m:=(~n&n-1).bit_length())&1 and (n>>m)&7==7,count(max(startvalue,1)))
%o A055039_list = list(islice(A055039_gen(),30)) # _Chai Wah Wu_, Jul 09 2022
%Y Equals twice A004215. Not the same as A044075 - see A124169.
%Y Complement of A000401.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Jun 01 2000
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