login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A318645 Decimal expansion of the asymptotic density of e-perfect numbers (A054979). 2
8, 6, 9, 4, 1, 9, 3, 9, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

-2,1

LINKS

Table of n, a(n) for n=-2..6.

Peter Hagis, Some results concerning exponential divisors, International Journal of Mathematics and Mathematical Sciences, Vol. 11 No. 2 (1988), pp. 343-349.

Eric Weisstein's World of Mathematics, e-Perfect Number

FORMULA

Equals Sum_{i>=1} beta(e(i))/e(i), where beta(n) = (6/Pi^2)*Product_{p|n}(p/(p+1)) and e(i) = A054980(i).

EXAMPLE

0.00869419399...

CROSSREFS

Cf. A049419, A051377, A054979, A054980.

Sequence in context: A084893 A019939 A343061 * A021096 A021119 A256686

Adjacent sequences:  A318642 A318643 A318644 * A318646 A318647 A318648

KEYWORD

nonn,cons,more

AUTHOR

Amiram Eldar, Aug 31 2018

EXTENSIONS

Offset corrected by Jianing Song, Feb 06 2019

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 27 15:36 EST 2021. Contains 349394 sequences. (Running on oeis4.)