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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A082506 a(n) = gcd(2^n, n - phi(n)); largest power of 2 dividing cototient(n) = A051953(n). 1
2, 1, 1, 2, 1, 4, 1, 4, 1, 2, 1, 8, 1, 8, 1, 8, 1, 4, 1, 4, 1, 4, 1, 16, 1, 2, 1, 16, 1, 2, 1, 16, 1, 2, 1, 8, 1, 4, 1, 8, 1, 2, 1, 8, 1, 8, 1, 32, 1, 2, 1, 4, 1, 4, 1, 32, 1, 2, 1, 4, 1, 32, 1, 32, 1, 2, 1, 4, 1, 2, 1, 16, 1, 2, 1, 8, 1, 2, 1, 16, 1, 2, 1, 4, 1, 4, 1, 16, 1, 2, 1, 16, 1, 16, 1, 64, 1, 8, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n)=1 if and only if n is odd or n = 2. - Robert Israel, May 31 2018

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

Different from A069177, analogous sequence with totient, instead of cototient.

MAPLE

f:= n -> padic:-ordp(n - numtheory:-phi(n), 2):

map(f, [$1..100]); # Robert Israel, May 31 2018

CROSSREFS

Cf. A000010, A051953, A009195, A083250, A007283, A050339, A053576, A069177.

Sequence in context: A113926 A276376 A165585 * A053000 A002070 A326376

Adjacent sequences: A082503 A082504 A082505 * A082507 A082508 A082509

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 28 2003

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 4 02:16 EST 2022. Contains 358544 sequences. (Running on oeis4.)