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A212143
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Number of (w,x,y,z) with all terms in {1,...,n} and w <= (geometric mean of x,y,z).
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2
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0, 1, 9, 39, 121, 285, 579, 1069, 1815, 2904, 4396, 6417, 9060, 12448, 16704, 21969, 28414, 36153, 45393, 56272, 69012, 83814, 100888, 120447, 142692, 167944, 196341, 228231, 263815, 303435, 347295, 395794, 449244, 507867, 572014
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OFFSET
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0,3
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COMMENTS
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LINKS
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MATHEMATICA
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t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[w^3 <= x*y*z, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 50]] (* A212143 *)
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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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