Today’s entry is a Theorem of the Day:
The Euclid-Euler Theorem:
An even positive integer is a perfect number, that is, equals the sum of its proper divisors, if and only if it has the form $2^{n−1}(2^n − 1)$, for some n such that $2^n − 1$ is prime.
This theorem describes the relationship between perfect numbers and Mersenne primes. For more information, see the full listing at Theorem of the Day: the Euclid-Euler Theorem.
This is part of the Aperiodical Advent Calendar. We’ll be posting a new surprise for you each morning until Christmas!
prof prem raj pushpakaran writes — let us celebrate eDay (Euler’s number or Napier’s constant) on February 7 !!!!