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%I #47 Jul 09 2022 11:06:42
%S 3,11,12,19,27,35,43,44,48,51,59,67,75,76,83,91,99,107,108,115,123,
%T 131,139,140,147,155,163,171,172,176,179,187,192,195,203,204,211,219,
%U 227,235,236,243,251,259,267,268,275,283,291,299,300,304
%N Numbers of the form 4^i*(8*j+3).
%C Numbers not of the form x^2+y^2+5z^2.
%C Also values of n such that numbers of the form x^2+n*y^2 for some integers x, y cannot have prime factor of 2 raised to an odd power. - _V. Raman_, Dec 18 2013
%H L. J. Mordell, <a href="https://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).
%F a(n) = 6n + O(log n). - _Charles R Greathouse IV_, Dec 19 2013
%o (PARI) is(n)=n/=4^valuation(n,4); n%8==3 \\ _Charles R Greathouse IV_ and _V. Raman_, Dec 19 2013
%o (Python)
%o from itertools import count, islice
%o def A055046_gen(startvalue=1): # generator of terms >= startvalue
%o return filter(lambda n:not (m:=(~n&n-1).bit_length())&1 and (n>>m)&7==3,count(max(startvalue,1)))
%o A055046_list = list(islice(A055046_gen(),30)) # _Chai Wah Wu_, Jul 09 2022
%Y Cf. A004215, A055045, A055047, A233998, A233999, A234000.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jun 01 2000
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