login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A072814 Smallest exponents of perfect powers: A001597(n)=A072813(n)^a(n). 1
2, 2, 3, 2, 2, 2, 3, 5, 2, 2, 2, 2, 2, 2, 3, 7, 2, 2, 2, 3, 2, 5, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 11, 2, 7, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 5, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..89.

Eric Weisstein's World of Mathematics, Perfect Power.

MATHEMATICA

{2}~Join~Map[Function[m, Min@ DeleteCases[#, x_ /; x < 2] &@ Table[Boole[k^# == m] # &@ IntegerExponent[m, k], {k, 2, Floor@ Sqrt@ m}]], Select[Range@ 5000, GCD @@ FactorInteger[#][[All, -1]] > 1 &]] (* Michael De Vlieger, Dec 08 2016 *)

CROSSREFS

Sequence in context: A160821 A300225 A060244 * A196229 A191302 A161189

Adjacent sequences:  A072811 A072812 A072813 * A072815 A072816 A072817

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 12 2002

EXTENSIONS

Definition corrected by Daniel Forgues, Mar 07 2009

Inserted a(1) = 2 by Gionata Neri, Dec 08 2016

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 May 26 13:05 EDT 2019. Contains 323586 sequences. (Running on oeis4.)