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A070929
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Smallest integer >=0 of the form x^2-n^3.
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5
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0, 0, 1, 9, 0, 19, 9, 18, 17, 0, 24, 38, 36, 12, 65, 106, 0, 128, 97, 30, 100, 148, 168, 154, 100, 0, 113, 198, 249, 260, 225, 138, 356, 163, 297, 389, 0, 423, 353, 217, 9, 248, 441, 17, 80, 79, 8, 506, 297, 0, 316, 574, 17, 119, 145, 89, 784, 568, 252, 737, 225, 548
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OFFSET
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0,4
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COMMENTS
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a(n)=0 iff n is a square.
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LINKS
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Table of n, a(n) for n=0..61.
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FORMULA
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a(n) = ceil(n^(3/2))^2 - n^3 = A077115(n) - n^3.
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EXAMPLE
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A077115(10)=1024=32^2 is the least square >= 10^3=1000, therefore a(10)=1024-1000=24.
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MATHEMATICA
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f[n_]=Ceiling[n^(3/2)]^2-n^3;
t1=Table[f[n], {n, 1, 90}]; t1 (* Clark Kimberling, Jan 30 2011 *)
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PROG
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(PARI) for(n=1, 100, print1(ceil(n^(3/2))^2-n^3, ", "))
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CROSSREFS
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Cf. A000578, A077116, A077118, A077119, A077109, A068527.
Sequence in context: A062047 A117465 A136679 * A007394 A067153 A057405
Adjacent sequences: A070926 A070927 A070928 * A070930 A070931 A070932
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KEYWORD
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easy,nonn
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AUTHOR
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Benoit Cloitre, May 20 2002
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STATUS
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approved
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