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A306403
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The number of distinct products that can be formed by multiplying the parts of a partition of n into 3 positive parts.
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2
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0, 0, 0, 1, 1, 2, 3, 4, 5, 7, 8, 10, 12, 13, 14, 19, 20, 23, 27, 29, 32, 34, 39, 43, 47, 51, 53, 59, 58, 67, 73, 75, 81, 88, 91, 93, 106, 109, 114, 117, 128, 131, 133, 145, 154, 163, 166, 174, 181, 180, 201, 206, 209, 219, 231, 240, 238, 252, 267, 272, 289, 290, 300, 299, 323, 328, 345, 349, 366, 376
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OFFSET
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0,6
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LINKS
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FORMULA
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MAPLE
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a:= proc(n) option remember; local m, c, i, j, h, w;
m, c:= proc() true end, 0; forget(m);
for i to iquo(n, 3) do for j from i to iquo(n-i, 2) do
h:= i*j*(n-j-i); w:= m(h);
if w then m(h):= false; c:= c+1 fi
od od; c
end:
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MATHEMATICA
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a[n_] := a[n] = Module[{m, c = 0, i, j, h, w}, m[_] = True; For[i = 1, i <= Quotient[n, 3], i++, For[j = i, j <= Quotient[n - i, 2], j++, h = i*j*(n - j - i); w = m[h]; If[w, m[h] = False; c++]]]; c];
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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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