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A211515
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Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^3=x*y.
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2
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0, 1, 1, 1, 3, 3, 3, 3, 6, 8, 8, 8, 8, 8, 8, 8, 10, 10, 12, 12, 12, 12, 12, 12, 14, 16, 16, 21, 21, 21, 21, 21, 25, 25, 25, 25, 27, 27, 27, 27, 29, 29, 29, 29, 29, 29, 29, 29, 31, 33, 35, 35, 35, 35, 39, 39, 41, 41, 41, 41, 41, 41, 41, 41, 48, 48, 48, 48, 48, 48, 48
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OFFSET
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0,5
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COMMENTS
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For a guide to related sequences, see A211422.
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LINKS
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FORMULA
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MATHEMATICA
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t[n_] := t[n] = Flatten[Table[w^3 - x*y, {w, 1, n}, {x, 1, n}, {y, 1, n}]]
c[n_] := Count[t[n], 0]
t = Table[c[n], {n, 0, 70}] (* A211515 *)
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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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