MathLabs

Problem 4

Find all positive integers nn such that {n,n+1,n+2,n+3,n+4,n+5}\{n,n+1,n+2,n+3,n+4,n+5\} can be partitioned into two disjoint sets whose products are equal.
Step 4 of 4: Reject the candidate
In plain words

An equal-product partition forces every prime exponent in the total product to be even.

5textoccurstoanoddpowerin1cdot2cdot3cdot4cdot5cdot65\\text{ occurs to an odd power in }1\\cdot2\\cdot3\\cdot4\\cdot5\\cdot6
Detailed analysis

In {1,2,3,4,5,6}\{1,2,3,4,5,6\}, the prime 55 divides exactly one element and occurs to the first power in the total product. An equal partition would make the total product a square, so this is impossible. Thus no positive nn works.