Computing GCDs of polynomials modulo triangular sets
نویسندگان
چکیده
We present a modular algorithm for computing GCDs of univariate polynomials with coefficients modulo a zero-dimensional triangular set. Our algorithm generalizes previous work for computing GCDs over algebraic number fields. The main difficulty is when a zero divisor is encountered modulo a prime number. We give two ways of handling this: Hensel lifting, and fault tolerant rational reconstruction. We compare the two methods with illustrative examples. Both approaches have been implemented in Maple using the RECDEN package.
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