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A211512
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Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2=3x*y.
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2
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0, 0, 0, 2, 2, 2, 6, 6, 6, 8, 8, 8, 14, 14, 14, 16, 18, 18, 22, 22, 22, 24, 24, 24, 30, 32, 32, 38, 38, 38, 44, 44, 46, 48, 48, 48, 56, 56, 56, 58, 58, 58, 62, 62, 62, 66, 66, 66, 76, 80, 82, 84, 84, 84, 92, 92, 92, 94, 94, 94, 104, 104, 104, 108, 112, 112, 116
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OFFSET
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0,4
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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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MATHEMATICA
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t[n_] := t[n] = Flatten[Table[w^2 - 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}] (* A211512 *)
t/2 (* integers *)
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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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