login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

Numbers that are not the sum of ten (10) positive cubes.
5

%I #18 Apr 18 2024 13:47:54

%S 1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,18,19,20,21,22,23,25,26,27,28,29,

%T 30,32,33,34,35,37,39,40,41,42,44,46,47,48,49,51,53,54,55,56,58,60,61,

%U 63,65,67,68,70,72,74,75,77,79,81,82,84,86,89,91,93,96,98,100

%N Numbers that are not the sum of ten (10) positive cubes.

%C The sequence is finite, with last term a(99) = 374.

%H M. F. Hasler, <a href="/A332110/b332110.txt">Table of n, a(n) for n = 1..99</a> (full sequence).

%H Brennan Benfield and Oliver Lippard, <a href="https://arxiv.org/abs/2404.08193">Integers that are not the sum of positive powers</a>, arXiv:2404.08193 [math.NT], 2024. See p. 4.

%e The smallest positive numbers not in the sequence are:

%e 10 = 10 * 1^3, 17 = 2^3 + 9 * 1^3, 24 = 2 * 2^3 + 8 * 1^3,

%e 31 = 3 * 2^3 + 7 * 1^3 and then 36 = 3^3 + 9 * 1^3.

%e The last 10 terms of the sequence are a(90 .. 99) = {196, 201, 208, 215, 222, 257, 294, 313, 320, 374}.

%t Select[Range[400], (pr = PowersRepresentations[#, 10, 3][[;; , 1]]) == {} || Max[pr] == 0 &] (* _Amiram Eldar_, Aug 24 2020 *)

%o (PARI) A332110=setminus([1..444],A003333_upto(555))

%Y Complement of A003333.

%Y Cf. A332107, A332108, A332109, A332111 (analog for 7, 8, 9, resp. 11 cubes).

%K nonn,fini,full

%O 1,2

%A _M. F. Hasler_, Aug 24 2020