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The minimal sequence from solving n^3 - m^2 = a(n).
(Formerly M0033 N0008)
4

%I M0033 N0008 #38 Oct 21 2023 06:34:41

%S 0,1,2,0,4,9,18,17,0,24,35,36,12,40,11,0,13,56,30,79,45,39,67,100,0,

%T 113,83,48,53,104,138,7,163,100,26,0,28,116,217,9,248,104,17,80,79,8,

%U 139,297,0,316,155,17,119,145,89,55,293,252,170,225,405,184,47,0,49

%N The minimal sequence from solving n^3 - m^2 = a(n).

%D Marshall Hall, Jr., The Diophantine equation x^3-y^2=k, pp. 173-198 of A. O. L. Atkin and B. J. Birch, editors, Computers in Number Theory. Academic Press, NY, 1971.

%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H T. D. Noe, <a href="/A002938/b002938.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = |A077119(n+1)|.

%F a(n^2) = 0. - _Benoit Cloitre_, Aug 17 2002

%t f1[n_] := n - Floor[Sqrt[n]]^2;

%t f2[n_] := Ceiling[Sqrt[n]]^2-n;

%t Table[Min[f1[n^3], f2[n^3]], {n,100}] (* _Vladimir Joseph Stephan Orlovsky_, Apr 08 2010 *)

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

%Y Cf. A077119.

%K nonn

%O 1,3

%A _N. J. A. Sloane_

%E More terms from _Benoit Cloitre_, Aug 17 2002