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A068095
All primes dividing each term are Fibonacci numbers.
1
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 13, 15, 16, 18, 20, 24, 25, 26, 27, 30, 32, 36, 39, 40, 45, 48, 50, 52, 54, 60, 64, 65, 72, 75, 78, 80, 81, 89, 90, 96, 100, 104, 108, 117, 120, 125, 128, 130, 135, 144, 150, 156, 160, 162, 169, 178, 180, 192, 195, 200
OFFSET
1,2
LINKS
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