On divisibility by nine of the sums of even amicable pairs

Author:
Elvin Lee

Journal:
Math. Comp. **23** (1969), 545-548

MSC:
Primary 10.07

DOI:
https://doi.org/10.1090/S0025-5718-1969-0248074-6

MathSciNet review:
0248074

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Abstract: Most known even amicable pairs have sums divisible by nine [9]. The general form of the exceptions to the rule of divisibility by nine (Gardner's rule) is deduced and the results expressed in the form of a theorem. A computer search based on a corollary to the theorem is described and six new exceptions to Gardner's rule are found.

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DOI:
https://doi.org/10.1090/S0025-5718-1969-0248074-6

Article copyright:
© Copyright 1969
American Mathematical Society