

A007539


First nfold perfect number.
(Formerly M4297)


16




OFFSET

1,2


COMMENTS

On the Riemann Hypothesis, a(n) > exp(exp(n / e^gamma)) for n > 3. Unconditionally, a(n) > exp(exp(0.9976n / e^gamma)) for n > 3, where the constant is related to A004394(1000000).  Charles R Greathouse IV, Sep 06 2012
Each of the terms 1, 6, 120, 30240 divides all larger terms <= a(8). See A227765, A227766, ..., A227769.  Jonathan Sondow, Jul 30 2013


REFERENCES

A. H. Beiler, Recreations in the Theory of Numbers, Dover, NY, 1964, p. 22.
A. Brousseau, Number Theory Tables. Fibonacci Association, San Jose, CA, 1973, p. 138.
R. K. Guy, Unsolved Problems in Number Theory, B2.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

T. D. Noe, Table of n, a(n) for n = 1..8
C. K. Caldwell, The Prime Glossary, multiply perfect
Achim Flammenkamp, The Multiply Perfect Numbers Page
Fred Helenius, Link to Glossary and Lists
Walter Nissen, Abundancy: Some Resources


CROSSREFS

Cf. A000396, A005820, A027687, A046060, A046061, A007691, A072002, A227765, A227766, A227767, A227768, A227769.
Sequence in context: A012475 A053777 A023199 * A040996 A110442 A137149
Adjacent sequences: A007536 A007537 A007538 * A007540 A007541 A007542


KEYWORD

nonn,nice


AUTHOR

N. J. A. Sloane.


EXTENSIONS

More terms sent by Robert G. Wilson v, Nov 30 2000


STATUS

approved



