OFFSET
1,3
COMMENTS
No more terms up to 6*10^5.
MATHEMATICA
n = 5 * 10^4.;
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)}];
Complement[Range[0, n], t]
CROSSREFS
KEYWORD
nonn,more
AUTHOR
XU Pingya, Jun 17 2020
STATUS
approved