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Numbers ending with '9' that are the difference of two positive cubes.
1

%I #14 Aug 09 2021 01:31:54

%S 19,169,189,279,469,819,919,999,1519,1899,2169,2189,2269,2619,3159,

%T 3169,3429,3789,4069,4219,4849,5409,5419,5489,5859,6669,6769,7839,

%U 7999,8269,8379,8749,9919,10439,10449,10719,11349,11529,11719,12159,13669,13699

%N Numbers ending with '9' that are the difference of two positive cubes.

%H Harvey P. Dale, <a href="/A038864/b038864.txt">Table of n, a(n) for n = 1..350</a>

%t dtcQ[n_]:=Total[Boole[Table[IntegerQ[Surd[k^3-n,3]],{k,Floor[ Surd[ n,3]]+1,100}]]]>0; Select[Range[9,14000,10],dtcQ] (* _Harvey P. Dale_, Aug 31 2020 *)

%K nonn,base

%O 1,1

%A _Jeff Burch_

%E Corrected by _Ray Chandler_, Nov 29 2008