Perfect Number/Sequence

Sequence of Perfect Numbers

The sequence of perfect numbers begins:

\(\ds 6\) \(=\) \(\ds 2^{2 - 1} \times \paren {2^2 - 1}\)
\(\ds 28\) \(=\) \(\ds 2^{3 - 1} \times \paren {2^3 - 1}\)
\(\ds 496\) \(=\) \(\ds 2^{5 - 1} \times \paren {2^5 - 1}\)
\(\ds 8128\) \(=\) \(\ds 2^{7 - 1} \times \paren {2^7 - 1}\)
\(\ds 33 \, 550 \, 336\) \(=\) \(\ds 2^{13 - 1} \times \paren {2^{13} - 1}\)
\(\ds 8 \, 589 \, 869 \, 056\) \(=\) \(\ds 2^{17 - 1} \times \paren {2^{17} - 1}\)

This sequence is A000396 in the On-Line Encyclopedia of Integer Sequences (N. J. A. Sloane (Ed.), 2008).


Sources

  • 1971: George E. Andrews: Number Theory ... (previous) ... (next): $\text {3-5}$ The Use of Computers in Number Theory
  • 1992: George F. Simmons: Calculus Gems ... (previous) ... (next): Chapter $\text {B}.2$: More about Numbers: Irrationals, Perfect Numbers and Mersenne Primes
  • 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): perfect number
  • 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): perfect number