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A297931
Numbers that are not the sum of a square and 3 nonnegative cubes.
0
15, 22, 23, 48, 86, 94, 112, 120, 139, 184, 203, 211, 230, 237, 263, 301, 309, 312, 335, 373, 399, 1014, 1056, 1455, 1644, 2029, 2272, 2658, 3309, 3469, 4019, 6502, 11101
OFFSET
1,1
COMMENTS
After 11101, there are no more terms up to 570000.
No more terms < 10^10; is this sequence finite? - Mauro Fiorentini, Jan 26 2019
LINKS
Eric Weisstein's World of Mathematics, Waring's Problem
MATHEMATICA
t1={};
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}];
t2={};
Do[If[FreeQ[t1, k]==True, AppendTo[t2, k]], {k, 0, 5.7*10^5}];
t2
CROSSREFS
KEYWORD
nonn
AUTHOR
XU Pingya, Jan 08 2018
STATUS
approved