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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A053476 Smallest number m such that when A051953 is applied n times to m the result is neither a power of 2 nor 0. 0
9, 21, 42, 82, 130, 330, 450, 666, 1050, 1470, 1950, 2922, 4074, 5586, 7770, 11154, 15810, 22638, 30702, 42570, 53130, 68970, 107690, 159390, 206910, 289830, 395190, 610350, 823290, 1185570, 1522290, 2168250, 3011850, 4103490, 5364450 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

An analog for A000005 is A049117.

LINKS

Table of n, a(n) for n=1..35.

FORMULA

Applying cototient-function A051953 n+1 times to a(n), a power of 2 or 0 appears; a(n) is the smallest with this property.

EXAMPLE

a(6)=330 and the iteration of A051953 applied to 330 gives sequence {330,250,150,110,70,46,24,16,8,4,2,1,0}. Six iterations result in the 6th term 24 which still is neither a power of 2 nor 0. For smaller numbers than 330 these 6 iterations yield a power of 2 or the fixed number 0.

CROSSREFS

Cf. A051953, see also its iterates.

Sequence in context: A110209 A184040 A242990 * A110680 A163205 A154862

Adjacent sequences:  A053473 A053474 A053475 * A053477 A053478 A053479

KEYWORD

nonn

AUTHOR

Labos Elemer, Jan 14 2000

EXTENSIONS

More terms from Jud McCranie, Jan 14 2000

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 18 04:44 EST 2019. Contains 329248 sequences. (Running on oeis4.)