A181056 a(n) = prime(phi(Fibonacci(n))).

2, 2, 2, 3, 7, 7, 37, 37, 53, 173, 457, 223, 1459, 2267, 1511, 4003, 13463, 9311, 38197, 29443, 49033, 193093, 333227, 136069, 746773, 1592923, 1157579, 2575043, 7594759, 4073233, 21225769, 19112567, 28016189, 98825561, 119488379, 75032131, 446083661, 729322973

Offset: 1

Author

Carmine Suriano, Oct 01 2010

Keywords

• nonn

Comments

Phi is Euler's totient function A000010.

Examples

			a(7) = 37 since prime(phi(fib(7))) = prime(phi(13)) = prime(12) = 37 is the 12th prime.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..85 (terms 1..60 from Vincenzo Librandi)

Crossrefs

Cf. A000010, A000040, A000045, A065449, A181058.

Programs

Magma

[NthPrime(EulerPhi(Fibonacci(n))): n in [1..40]]; // Vincenzo Librandi, Jun 23 2014

Maple

A065449 := proc(n) numtheory[phi](combinat[fibonacci](n)) ; end proc: A181056 := proc(n) ithprime(A065449(n)) ; end proc: seq(A181056(n),n=1..32) ; # R. J. Mathar, Oct 02 2010

Mathematica

Prime[EulerPhi[Fibonacci[Range[35]]]] (* Harvey P. Dale, Jun 22 2014 *)

Formula

a(n) = A000040(A065449(n)). - R. J. Mathar, Oct 02 2010

Extensions

a(1) inserted by R. J. Mathar, Oct 02 2010