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Oh, my eyes, my eyes! People still can solve this kind of cryptography? Mathematicians should love this one!
Files given:
Looking at the image, it looks like some latex output:

and we can copy out the latex as
tex
\Cap\Cap\Theta\Finv\\{\Pi\ltimes\aleph y\_\wp\infty\therefore\heartsuit\_\Lsh\aleph\Theta\eth\Xi\\}and read off the flag