login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A022555 Positive integers that are not the sum of two nonnegative cubes. 5
3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 29, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 62, 63, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Omits the positive cubes (A000578) since m^3 = 0^3 + m^3, so is different from A057903.

LINKS

T. D. Noe, Table of n, a(n) for n=1..10000

Index entries for sequences related to sums of cubes

MAPLE

read transforms; cub := series(add(q^(n^3), n=0..100), q, 1000001); t1 := series(cub^2, q, 2000); t2 := POWERS(t1, q, 2000); COMPl(t2);

MATHEMATICA

r[n_] := Reduce[x >= 0 && y >= 0 && n == x^3 + y^3, {x, y}, Integers]; Select[ Range[80], r[#] === False &]  (* Jean-Fran├žois Alcover, Nov 06 2012 *)

Select[Range@100, PowersRepresentations[#, 2, 3]=={}&] (* A much faster solution given by Giovanni Resta, Nov 06 2012 *)

CROSSREFS

Complement of A004999. Cf. A004825, A022561, A022566, A057903, A000578.

Sequence in context: A139372 A226116 A128659 * A047308 A092860 A112874

Adjacent sequences:  A022552 A022553 A022554 * A022556 A022557 A022558

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Edited by N. J. A. Sloane, Sep 28 2007

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified September 24 04:14 EDT 2017. Contains 292402 sequences.