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!)
A278350 Cototient of Fibonacci(n). 0
0, 0, 1, 1, 1, 4, 1, 9, 18, 15, 1, 96, 1, 41, 370, 435, 1, 1432, 149, 3565, 5906, 287, 1, 33696, 15025, 753, 106562, 129651, 1, 544040, 2973, 960597, 1782178, 5167, 2413385, 10534320, 501497, 1397033, 31758946, 60862155, 62157, 149373496, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

COMMENTS

a(n) = 1 if Fibonacci(n) is prime.

LINKS

Table of n, a(n) for n=1..43.

FORMULA

a(n) = A051953(A000045(n)).

a(n) = A000045(n) - A065449(n) for n > 0.

MATHEMATICA

Table[Fibonacci[n] - EulerPhi[Fibonacci[n]], {n, 40}] (* Alonso del Arte, Nov 21 2016 *)

PROG

(PARI) a(n) = fibonacci(n) - eulerphi(fibonacci(n));

CROSSREFS

Cf. A000045, A051953, A065449.

Sequence in context: A075150 A001254 A143763 * A128626 A193963 A028941

Adjacent sequences:  A278347 A278348 A278349 * A278351 A278352 A278353

KEYWORD

nonn

AUTHOR

Altug Alkan, Nov 19 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 January 20 03:25 EST 2022. Contains 350467 sequences. (Running on oeis4.)