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Kaprekar triples: q^3 = x*10^2n + y*10^n + z, with q = x + y + z and 10^n > q > 10^(n-1) (q = 1 allowed for n = 1).
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%I #16 Feb 24 2018 11:50:07

%S 1,512,91125,26198073,12519490248,20301732352,87824421125,93824221184,

%T 121213882349,128711132649,162324571375,171323771464,368910352448,

%U 19902511000000,87782935806307,171471879319616,220721185826504,470511577514952,2977097087043793,9063181647017784

%N Kaprekar triples: q^3 = x*10^2n + y*10^n + z, with q = x + y + z and 10^n > q > 10^(n-1) (q = 1 allowed for n = 1).

%H Hans Havermann, <a href="/A291461/b291461.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A006887(n)^3.

%o (PARI) m=10; for(q=1,1e4,if(q<m,q==sumdigits(q^3,m)&&print1(q^3,","),m*=10)) \\ See A006887 for slightly more efficient code.

%Y Cf. A006887.

%K nonn,base

%O 1,2

%A _M. F. Hasler_, Aug 24 2017