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List of pairs (Posted on 2015-12-04) Difficulty: 2 of 5
There are infinitely many ordered pairs (m,n) of positive integers for which
m + (m+1) + (m+2) + ... (n-1) + n = mn.

List the first five pairs ordered by values of m.

No Solution Yet Submitted by Ady TZIDON    
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re: computer solution -- first eight pairs | Comment 2 of 3 |
(In reply to computer solution -- first eight pairs by Charlie)

That's about as far as I got: searching quadratic formulas for m that give and integer.

m is given by  https://oeis.org/A011900
n is given by https://oeis.org/A001109
each note a recursion relation.  I'm trying to prove it.

  Posted by Jer on 2015-12-04 12:50:00
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