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Minimum value of abs(n^2-x^3) x>0.
0

%I #14 Feb 12 2014 22:00:18

%S 0,3,1,8,2,9,15,0,17,25,4,19,44,20,9,40,54,19,18,57,71,28,17,64,104,

%T 53,0,55,112,100,39,24,89,156,106,35,38,113,190,128,47,36,121,208,172,

%U 81,12,107,204,244,143,40,65,172,281,239,126,11,106,225,346,252,127,0,129

%N Minimum value of abs(n^2-x^3) x>0.

%F a(n^3) = 0.

%F a(n) = abs(A077111(n)). - _R. J. Mathar_, May 01 2008

%t Table[Min[n^2-Floor[(n^2)^(1/3)]^3,(Floor[(n^2)^(1/3)]+1)^3-n^2],{n,100}] (* _Vladimir Joseph Stephan Orlovsky_, Feb 01 2012 *)

%o (PARI) a(n)=vecmin(vector(ceil(n^(2/3)),i,abs(n^2-i^3)))

%Y Cf. A002938.

%K easy,nonn

%O 1,2

%A _Benoit Cloitre_, Aug 17 2002