%I #16 Jul 08 2017 01:24:35
%S 0,1,2,4,5,7,8,9,10,11,12,13,15,16,17,18,20,23,24,25,26,27,28,29,30,
%T 32,33,34,36,37,38,39,40,41,43,44,45,46,47,48,49,50,52,53,54,56,57,58,
%U 59,60,61,62,63,64,65,67,68,69,71,72
%N Numbers of form x^2 + y^2 + 7z^2.
%t r[n_] := Reduce[n == x^2 + y^2 + 7z^2, {x, y, z}, Integers]; Reap[For[n = 0, n <= 100, n++, If[r[n] =!= False, Print[n]; Sow[n]]]][[2, 1]] (* _Jean-François Alcover_, Feb 08 2016 *)
%Y Complement of A097633.
%K nonn
%O 0,3
%A _N. J. A. Sloane_