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Four integers (Posted on 2016-12-04)

Find four distinct positive integers such that:
a. Each of them is below 500.
b. Multiplying any two of them and then incrementing the product by 1
produces a square number.

No Solution Yet Submitted by Ady TZIDON

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re(4): Master of the obvious - beg to differ

Comment 8 of 8 |

(In reply to re(3): Master of the obvious - beg to differ by Ady TZIDON)

Well, I thought it was obvious, but if we eliminate the word "positive" then all of the following are solutions.

-1 -3 -8 -120

-1 -3 -120 -1680

-1 -8 -15 -528

-1 -15 -24 -1520

-2 -4 -12 -420

-3 -5 -16 -1008

Note that all of these numbers are less than 500.

Posted by Steve Herman on 2016-12-14 08:25:43

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