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A094906
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Numbers m such that m^3-k^3 is a square for some k<m.
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1
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1, 4, 8, 9, 10, 14, 16, 25, 28, 32, 33, 36, 40, 49, 56, 57, 64, 65, 71, 72, 74, 78, 81, 90, 100, 105, 112, 114, 121, 126, 128, 130, 132, 140, 144, 148, 154, 155, 160, 169, 176, 193, 196, 200, 217, 218, 224, 225, 228, 250, 252, 256, 260, 266, 273, 280, 284, 288
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) seems to be asymptotic to c*n^(3/2) where c = 0.49....
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EXAMPLE
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8^3-7^3 = 13^2 hence 8 is in the sequence.
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MATHEMATICA
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q[n_] := AnyTrue[Range[0, n - 1], IntegerQ@Sqrt[n^3 - #^3] &]; Select[Range[300], q] (* Amiram Eldar, May 08 2022 *)
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PROG
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(PARI) for(n=1, 420, if(sum(i=0, n-1, issquare(n^3-i^3))>0, print1(n, ", ")))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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