$N$ terms of an AP are divisible by product of first $N$

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rah4927
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$N$ terms of an AP are divisible by product of first $N$

Unread post by rah4927 » Thu Nov 10, 2016 1:08 pm

Find all Arithmetic progressions $a_{1},a_{2},...$ of natural numbers for which there exists natural number $N>1$ such that for every $k\in \mathbb{N}$:

$a_{1}a_{2}...a_{k}\mid a_{N+1}a_{N+2}...a_{N+k}$

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