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A093670
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Numbers having a unique representation as ab+ac+bc, with 1 <= a <= b <= c.
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4
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3, 5, 7, 8, 9, 12, 13, 14, 16, 25, 28, 34, 37, 46, 82, 142
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OFFSET
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1,1
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COMMENTS
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Are there more terms?
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REFERENCES
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LINKS
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EXAMPLE
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25 is on the list because 25 = 1*1 + 1*12 + 1*12.
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MATHEMATICA
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oneSol={}; Do[lim=Ceiling[(n-1)/2]; cnt=0; Do[If[n>a*b && Mod[n-a*b, a+b]==0 && Quotient[n-a*b, a+b]>=b, cnt++; If[cnt>1, Break[]]], {a, 1, lim}, {b, a, lim}]; If[cnt==1, AppendTo[oneSol, n]], {n, 10000}]; oneSol
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CROSSREFS
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Cf. A025052 (numbers not of the form ab+ac+bc, 1<=a<=b<=c).
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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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