OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
Sum_{n>=1} 1/a(n) = Product_{p in A005478} p/(p-1) = 4.12911211011314367889... - Amiram Eldar, Sep 27 2020
EXAMPLE
26 = 2 * 13 is a term since 2 and 13 are both primes and Fibonacci numbers.
MATHEMATICA
p = Fibonacci[{2, 3, 4, 5, 7, 11, 13}]; Select[Range[p[[-1]]], AllTrue[ FactorInteger[#][[;; , 1]], MemberQ[p, #] &] &] (* Amiram Eldar, Sep 27 2020 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Leroy Quet, Mar 22 2002
EXTENSIONS
a(1)=1 added and offset corrected by Amiram Eldar, Sep 27 2020
STATUS
approved