OFFSET
1,1
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..1000
EXAMPLE
89 divides both 2^11-1=2047 and Fibonacci(11)=89, so 11 is in the sequence.
MATHEMATICA
Select[Prime[Range[8000]], GCD[2^#-1, Fibonacci[#]]>1&] (* Harvey P. Dale, Mar 16 2020 *)
PROG
(PARI) forprime(p=1, 10^5, if(gcd(2^p-1, fibonacci(p))>1, print(p))).
CROSSREFS
KEYWORD
nonn
AUTHOR
Ralf Stephan, Jan 22 2003
STATUS
approved