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A054221 without cubes.
1

%I #15 Jan 15 2019 02:02:14

%S 7,10,23,48,199,621,978,1222,3563,4034,4331,5017,6442,6886,7783,8699,

%T 11157,12287,12386,30258,30525,31629,35461,49250,52737,55404,64356,

%U 65191,72178,119109,120806,126941

%N A054221 without cubes.

%H Bert Dobbelaere, <a href="/A054224/b054224.txt">Table of n, a(n) for n = 0..57</a>

%t max = 20000; s = {}; Do[ k = ((i*(i+1)*(i+2) - j*(j+1)*(j+2))/6)^(1/3); If[IntegerQ[k] && !IntegerQ[i^(1/3)], Print[i]; AppendTo[s, i]], {j, 1, max}, {i, j+1, max}]; Sort[s] (* _Jean-François Alcover_, Dec 20 2012 *)

%Y Cf. A054221.

%K nice,nonn

%O 0,1

%A Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Feb 04 2000

%E Extended to 19 terms by _Jean-François Alcover_, Dec 20 2012

%E More terms from _Joerg Arndt_, Apr 06 2013