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%I #18 Jan 26 2019 12:15:00
%S 15,22,23,48,86,94,112,120,139,184,203,211,230,237,263,301,309,312,
%T 335,373,399,1014,1056,1455,1644,2029,2272,2658,3309,3469,4019,6502,
%U 11101
%N Numbers that are not the sum of a square and 3 nonnegative cubes.
%C After 11101, there are no more terms up to 570000.
%C No more terms < 10^10; is this sequence finite? - _Mauro Fiorentini_, Jan 26 2019
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/WaringsProblem.html">Waring's Problem</a>
%t t1={};
%t Do[Do[If[x^2+y^2+z^2+w^3==n, AppendTo[t1,n]&&Break[]], {x,0,n^(1/2)}, {y,x,(n-x^2)^(1/2)}, {z,y,(n-x^2-y^2)^(1/2)}, {w,0,(n-x^2-y^2-z^2)^(1/3)}], {n,0,5.7*10^5}];
%t t2={};
%t Do[If[FreeQ[t1,k]==True, AppendTo[t2,k]], {k,0,5.7*10^5}];
%t t2
%Y Cf. A004215, A022552, A022557, A022561, A022566, A111151.
%K nonn
%O 1,1
%A _XU Pingya_, Jan 08 2018
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