This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A335658 #5 Jul 08 2020 20:45:37
%S A335658 0,1,2,3,5,6,8,9,16,21,24,40
%N A335658 Numbers that are not the sum of 3 nonzero squares and a positive cube.
%C A335658 No more terms up to 6*10^5.
%t A335658 n = 5 * 10^4.;
%t A335658 t = Union@Flatten@Table[x^2 + y^2 + z^2 + w^3, {x,(n/3)^(1/2)}, {y,x,((n-x^2)/2)^(1/2)},{z,y,(n-x^2-y^2)^(1/2)}, {w,(n-x^2-y^2-z^2)^(1/3)}];
%t A335658 Complement[Range[0,n],t]
%Y A335658 Cf. A000534, A004214, A297788.
%K A335658 nonn,more
%O A335658 1,3
%A A335658 _XU Pingya_, Jun 17 2020