• Richard K. Guy
Part of the Unsolved Problems in Intuitive Mathematics book series (PBM, volume 1)


We will denote by d(n) the number of positive divisors of n, by σ(n) the sum of those divisors, and by σ k (n) the sum of their kth powers, so that σ 0(n) = d(n) and σ 1(n) = σ(n). We use s(n) for the sum of the aliquot parts of n, i.e., the positive divisors of n other than n itself, so that s(n) = σ(n) − n.


Unsolved Problem Prime Divisor Numerical Math Acta Arith Consecutive Integer 
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Copyright information

© Springer Science+Business Media New York 1981

Authors and Affiliations

  • Richard K. Guy
    • 1
  1. 1.Department of Mathematics and StatisticsThe University of CalgaryCalgaryCanada

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