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A002938
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The minimal sequence from solving n^3 - m^2 = a(n).
(Formerly M0033 N0008)
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4
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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, 113, 83, 48, 53, 104, 138, 7, 163, 100, 26, 0, 28, 116, 217, 9, 248, 104, 17, 80, 79, 8, 139, 297, 0, 316, 155, 17, 119, 145, 89, 55, 293, 252, 170, 225, 405, 184, 47, 0, 49
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OFFSET
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1,3
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REFERENCES
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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.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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MATHEMATICA
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f1[n_] := n - Floor[Sqrt[n]]^2;
f2[n_] := Ceiling[Sqrt[n]]^2-n;
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PROG
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(PARI) a(n)=vecmin(vector(ceil(n^(3/2)), i, abs(n^3-i^2)))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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