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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A286627 a(n) = exponent of the highest power of A000005(n) (number of divisors of n) dividing A000010(n) (totient function phi), a(1) = 1. 3
1, 0, 1, 0, 2, 0, 1, 1, 1, 1, 1, 0, 2, 0, 1, 0, 4, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 2, 1, 1, 0, 1, 2, 1, 0, 2, 0, 1, 1, 3, 0, 1, 0, 1, 0, 1, 0, 1, 0, 2, 1, 2, 0, 1, 1, 1, 1, 1, 0, 2, 0, 2, 0, 2, 0, 1, 0, 1, 1, 1, 1, 3, 1, 0, 2, 1, 1, 1, 0, 0, 1, 1, 1, 3, 0, 1, 1, 3, 1, 1, 0, 1, 0, 1, 0, 5, 1, 1, 0, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 0, 4, 0, 1, 0, 2, 0, 2, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,5
COMMENTS
a(1) = 1 by convention.
LINKS
FORMULA
a(n) = A286561(A000010(n), A000005(n)).
EXAMPLE
A000005(5) = 2, A000010(5) = 4, 2^2 is the highest power of 2 which divides 4, thus a(5) = 2.
A000005(6) = 4, A000010(6) = 2, 4^0 = 1 is the highest power of 4 which divides 2, thus a(6) = 0.
PROG
(PARI) A286627(n) = valuation(eulerphi(n), numdiv(n));
CROSSREFS
Cf. A015733 (positions of zeros), A020491 (of nonzeros).
Sequence in context: A353421 A105241 A134541 * A182071 A317992 A228085
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 30 2017
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 March 19 04:26 EDT 2024. Contains 370952 sequences. (Running on oeis4.)