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A178096
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Cube of n is equal to sum of four positive distinct squares; n^3=a^2+b^2+c^2+d^2; a>b>c>d>0.
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0
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5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57
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OFFSET
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1,1
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COMMENTS
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5^3=8^2+6^2+4^2+3^2, 6^3=10^2+8^2+6^2+4^2, ...
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LINKS
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FORMULA
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MATHEMATICA
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z=100; lst={}; Do[a2=a^2; Do[b2=b^2; Do[c2=c^2; Do[d2=d^2; e2=a2+b2+c2+d2; e=e2^(1/3); If[IntegerQ[e], AppendTo[lst, e]], {d, c-1, 1, -1}], {c, b-1, 1, -1}], {b, a-1, 1, -1}], {a, 1, z}]; Union@lst
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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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