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A330708 Numbers that are not the sum of 2 nonzero squares and a positive cube. 1
0, 1, 2, 4, 5, 7, 8, 12, 15, 17, 20, 22, 23, 24, 31, 36, 39, 43, 50, 55, 57, 63, 65, 70, 71, 78, 87, 94, 103, 111, 113, 115, 119, 120, 134, 139, 141, 148, 160, 167, 169, 185, 204, 211, 254, 263, 267, 279, 283, 286, 302, 311, 312, 331, 335, 342, 349, 379, 391 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

A022552 is a subsequence.

a(490) = A022552(434) = 5042631. No more terms <= 4 * 10^7.

LINKS

Robert Israel, Table of n, a(n) for n = 1..490

MAPLE

N:= 500: # for terms <= N

G1:= add(x^(i^2), i=1..floor(sqrt(N))):

G2:= add(x^(i^3), i=1..floor(N^(1/3))):

G:= expand(G1^2*G2):

select(t -> coeff(G, x, t)=0, [$0..N]); # Robert Israel, Jun 12 2020

MATHEMATICA

m = 0;

n = 400.;

t = Union@Flatten@Table[x^2 + y^2 + z^3, {x, (n/2)^(1/2)}, {y, x, (n - x^2)^(1/2)}, {z, If[x^2 + y^2 < m, Floor[(m - 1 - x^2 - y^2)^(1/3)] + 1, 1], (n - x^2 - y^2)^(1/3)}];

Complement[Range[m, n], t]

CROSSREFS

Cf. A022552, A000534, A004214.

Sequence in context: A261188 A176193 A072920 * A107899 A032924 A005125

Adjacent sequences:  A330705 A330706 A330707 * A330710 A330711 A330712

KEYWORD

nonn

AUTHOR

XU Pingya, Jun 08 2020

STATUS

approved

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Last modified July 5 21:00 EDT 2020. Contains 335473 sequences. (Running on oeis4.)