Hi.

There are well-known algorithms for cryptography to compute modular exponentiation $a^b\%c$ (like Right-to-left binary method here : http://en.wikipedia.org/wiki/Modular_exponentiation).

But do algorithms exist to compute modular exponentiation of the form $a^{\left(2^N\right)}\%m$ faster than with "classical" algorithms ?

Thank you very much !

Notes :

1) $m$ has no particular property

2) $N < 2^{32}$

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