

A093670


Numbers having a unique representation as ab+ac+bc, with 1 <= a <= b <= c.


4



3, 5, 7, 8, 9, 12, 13, 14, 16, 25, 28, 34, 37, 46, 82, 142
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OFFSET

1,1


COMMENTS

Are there more terms?


REFERENCES

See A025052


LINKS

Table of n, a(n) for n=1..16.


EXAMPLE

25 is on the list because 25 = 1*1 + 1*12 + 1*12.


MATHEMATICA

oneSol={}; Do[lim=Ceiling[(n1)/2]; cnt=0; Do[If[n>a*b && Mod[na*b, a+b]==0 && Quotient[na*b, a+b]>=b, cnt++; If[cnt>1, Break[]]], {a, 1, lim}, {b, a, lim}]; If[cnt==1, AppendTo[oneSol, n]], {n, 10000}]; oneSol


CROSSREFS

Cf. A025052 (numbers not of the form ab+ac+bc, 1<=a<=b<=c).
Sequence in context: A229838 A191257 A120212 * A185011 A175144 A183054
Adjacent sequences: A093667 A093668 A093669 * A093671 A093672 A093673


KEYWORD

nonn


AUTHOR

T. D. Noe, Apr 08 2004


STATUS

approved



