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Sum of the digits of n exceeds the sum of the digits of n^2 and the sum of digits of n^3.
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%I #5 May 26 2015 08:08:29

%S 49639,496390,736968,4963900,7369680,7989889,8962888,49639000,

%T 73696800,79898890,89628880,284799946,467995756,468754968,479593884,

%U 479698887,493968877,496390000,736968000,789499856,795875871,796999858,798968787,798988900,896288800

%N Sum of the digits of n exceeds the sum of the digits of n^2 and the sum of digits of n^3.

%C Intersection of A064399 and A064209.

%H Giovanni Resta, <a href="/A258320/b258320.txt">Table of n, a(n) for n = 1..463</a> (terms < 2^(128/3))

%e n = 49639 is in the sequence because sod(n) = 31, sod(n^2) = 25 and sod(n^3) = 28. Here n^2 = 2464030321 and n^3 = 122312001104119.

%t sod[n_]:=Plus@@ IntegerDigits@ n; Select[Range[10^6], sod[#^3] < sod@# && sod[#^2] < sod@# &]

%Y Cf. A064399, A064209.

%K nonn,base

%O 1,1

%A _Giovanni Resta_, May 26 2015