We are given the expression
(n12020+n22019)(n22020+n32019)⋯(n20212020+n20222019)(n20222020+n12019)
and need to determine if it can be a power of 11, i.e., 11k for some k∈N.
To approach this problem, we can use modular arithmetic. Consider the expression modulo 11:
Each term in the product is of the form ni2020+ni+12019. For each positive integer ni not divisible by 11, one of ni2020, ni+12019 will not necessarily be 0mod11. Note that Fermat's Little Theorem tells us ni10≡1(mod11) (if ni is not divisible by 11), which can extend to show a periodic cycle for the powers involved:
1. ni2020=(ni10)202≡1202≡1(mod11).
2. ni2019=ni10×201⋅ni9≡1201⋅ni9≡ni9(mod11).
Now, observe the expression modulo 11:
ni2020+ni+12019≡1+ni+19(mod11)
To be a power of 11, if the entire product could somehow equate to 0(mod11), each term would need to individually be divisible by 11. Otherwise, no complete cancellation or modulus-induced zero can occur. Therefore, each ni2020+ni+12019≡0(mod11).
For ni2020+ni+12019≡0(mod11), we must have:
ni+19≡−1(mod11)
The power residue ni+19≡−1(mod11) introduces inconsistency because:
- ni9≡b(mod11) implies that there is no integer that squares to −1 (since −1 is not a quadratic residue mod 11).
Thus, by attempt to set ni2020+ni+12019=0(mod11) repeatedly contradictions to properties of mod can appear.
Hence, the conclusion is that it is impossible for the given product to be an integer power of 11 for any choice of positive integers n1,n2,…,n2022.
Therefore, the answer is:
No