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57129 resources
Juan L. Varona's work on aliquot sequences examines sequences with start values up to 10000, and traces them to large composite values.
A detailed history of the quest for perfect numbers, from Euclid to their present-day Mersenne discoveries.
Results and software from Paul Zimmermann, addressing the Catalan Conjecture and working on the difficult "Lehmer Five" sequences.
Observations on amicable pairs and their distribution, including Harshad and Happy Amicable pairs.
Up-to-date information on multiperfect numbers and searchable database maintained by Achim Flammenkamp.
Sequences with initial term up to 10,000, by Christophe Clavier.
Definitions and references.
Aliquot sequences arise in iterating the sum-of-divisors function s. Bosma has calculated tables up to start value 50,000 and 80 digits.
Statistics by Wolfgang Creyaufmueller, including many tables and links to factoring sites and software.