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Mathematics of Computation
Journal of the American Mathematical Society
ISSN 1088-6842(e) ISSN 0025-5718(p)
     

A new algorithm for constructing large Carmichael numbers

Author(s): Günter Löh; Wolfgang Niebuhr.
Journal: Math. Comp. 65 (1996), 823-836.
MSC (1991): Primary 11Y16; Secondary 11Y11, 11A51, 11--04
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Abstract: We describe an algorithm for constructing Carmichael numbers $N$ with a large number of prime factors $p_{1}, p_{2}, \dots , p_{k}$. This algorithm starts with a given number $\Lambda =\operatorname {lcm} (p_{1}-1, p_{2}-1, \dots ,p_{k}-1)$, representing the value of the Carmichael function $\lambda (N)$. We found Carmichael numbers with up to $1101518$ factors.


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Additional Information:

Günter Löh
Affiliation: Regionales Rechenzentrum der Universität Hamburg, Schlüterstraße 70, 20146 Hamburg, Germany
Email: rz2a011@rrz.uni-hamburg.de

Wolfgang Niebuhr
Affiliation: Regionales Rechenzentrum der Universität Hamburg, Schlüterstraße 70, 20146 Hamburg, Germany
Address at time of publication: Lisztstraße~6b, 22763 Hamburg, Germany
Email: 100117.256@compuserve.com

DOI: 10.1090/S0025-5718-96-00692-8
PII: S 0025-5718(96)00692-8
Keywords: Carmichael number, absolute pseudoprime, Carmichael function, algorithm
Received by editor(s): November 6, 1992
Received by editor(s) in revised form: October 11, 1994 and February 12, 1995
Copyright of article: Copyright 1996, American Mathematical Society


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