%I #44 Mar 28 2019 00:47:17
%S 7,10,14,15,21,30,35,39,42,63,70,79,84,91,94,119,126,130,133,140,168,
%T 175,182,189,210,217,231,238,259,266,280,287,315,329,336,343,359,364,
%U 378,382,385,391,399,413,427,434,462,476,483,490,511,525,532,546,560
%N Numbers not of the form x^2+2*y^2+2*y*z+4*z^2 (with x, y, z all >= 0).
%C It appears that the only terms not divisible by 7 are 10, 15, 30, 39, 79, 94, 130, 359, 382, 391, 754, and 1546.  _Robert Israel_, Mar 27 2019
%H Robert Israel, <a href="/A306469/b306469.txt">Table of n, a(n) for n = 1..10000</a>
%H Irving Kaplansky, <a href="https://doi.org/10.1090/S00255718199512650172">The first nontrivial genus of positive definite ternary forms</a>, Mathematics of Computation, Vol. 64 (1995): 341345.
%p N:= 1000: # for terms <= N
%p V:= Array(0..N):
%p for x from 0 while x^2<=N do
%p for y from 0 while x^2 + 2*y^2 <= N do
%p for z from 0 do
%p v:= x^2 + 2*y^2 + 2*y*z + 4*z^2;
%p if v > N then break fi;
%p V[v]:= 1;
%p od od od:
%p select(t > V[t]=0, [$1..N]); # _Robert Israel_, Mar 27 2019
%Y Cf. A097634 (without the nonnegative requirement).
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Mar 26 2019
%E Thanks to _Robert Israel_ for pointing out that I neglected to mention x, y, z >= 0.  _N. J. A. Sloane_, Mar 27 2019
