The OEIS is supported by the many generous donors to the OEIS Foundation.

 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 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified March 30 06:16 EDT 2023. Contains 361606 sequences. (Running on oeis4.)