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PowerMod    --    compute a modular power efficiently

Syntax

PowerMod(A: INT, B: INT, M: INT): INT

Description

This function calculates efficiently an integer power modulo a given modulus. Thus PowerMod(A, B, M) is equal to mod(A^B, M), but the former is computed faster. If A and M are coprime then B may be negative.

Example

/**/ PowerMod(12345,41041,41041); -- 41041 is a Carmichael number 12345 /**/ PowerMod(123456789,987654321,32003); -- cannot compute 123456789^987654321 directly 2332