Problem - 02 - National Math Camp 2021 Mock Exam - "Modular equation involving power tower of 2"
Posted: Thu May 13, 2021 12:08 am
Let $n = 2^{2^x}$ for some $x > 0$. If $d\mid n^2+1$, then show that \[d\equiv1\pmod{2^{x+3}}\]
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