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Zeroless numbers n with digits d_1, d_2, ... d_k such that d_1^3 + ... + d_k^3 is a cube.
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%I #11 Sep 23 2019 16:29:33

%S 1,2,3,4,5,6,7,8,9,168,186,345,354,435,453,534,543,618,681,816,861,

%T 1156,1165,1516,1561,1615,1651,5116,5161,5611,6115,6151,6511,11233,

%U 11323,11332,12133,12313,12331,13123,13132,13213,13231,13312,13321,13369,13396,13458,13485,13548,13584,13639,13693,13845,13854

%N Zeroless numbers n with digits d_1, d_2, ... d_k such that d_1^3 + ... + d_k^3 is a cube.

%C Any one of these terms can have an arbitrary number of 0's in between any two digits. Thus, the numbers with 0's have been omitted as trivial.

%H Jonathan Schwartz, <a href="/A254960/b254960.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[14000],DigitCount[#,10,0]==0&&IntegerQ[Surd[Total[ IntegerDigits[ #]^3],3]]&] (* _Harvey P. Dale_, Sep 23 2019 *)

%o (PARI) for(n=1,10^3,d=digits(n);if(vecsort(d,,8)[1],s=0;for(i=1,#d,s+=d[i]^3);if(ispower(s,3),print1(n,", "))))

%Y Cf. A000578, A225535.

%K nonn,base

%O 1,2

%A _Derek Orr_, Feb 11 2015