If k is a non-negative integer and 21^k is a divisor of…

If k is a non-negative integer and 21^k is a divisor of 435,961 then 7^k - k^7 =

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #318