Robust HGCD with No Backup Steps

  • Niels Möller
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4151)


Subquadratic divide-and-conquer algorithms for computing the greatest common divisor have been studied for a couple of decades. The integer case has been notoriously difficult, with the need for “backup steps” in various forms. This paper explains why backup steps are necessary for algorithms based directly on the quotient sequence, and proposes a robustness criterion that can be used to construct a “half-gcd” algorithm without any backup steps.


Great Common Divisor Recursive Call Algorithm Return Continue Fraction Expansion Robustness Condition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Niels Möller
    • 1
  1. 1.KTHSchool of Electrical EngineeringStockholmSweden

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