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A272331
Refactorable Fibonacci numbers.
0
1, 2, 8, 46368, 4807526976
OFFSET
1,2
COMMENTS
Luca & Young prove that there are no more terms in this sequence. - Charles R Greathouse IV, Apr 27 2016
FORMULA
a(n) = A000045(A160683(n+1)). - Michel Marcus, Apr 25 2016
EXAMPLE
8 is a term as a Fibonacci number that is divisible by the number of its divisors, (1,2,4,8), which is 4.
MAPLE
select(t -> t mod numtheory:-tau(t) = 0, map(combinat:-fibonacci, [$2..200])); # Robert Israel, Apr 27 2016
MATHEMATICA
DeleteDuplicates@Select[Fibonacci@Range@200, Divisible[#, IntegerLength@#]&]
PROG
(PARI) for(n=2, 200, fn=fibonacci(n); fn%numdiv(fn)==0&&print1(fn ", "))
CROSSREFS
Intersection of A000045 (Fibonacci numbers) and A033950 (refactorable numbers).
Cf. A000005 (number of divisors), A160683.
Sequence in context: A185681 A046967 A007753 * A256065 A081979 A012672
KEYWORD
nonn,fini,full
AUTHOR
Waldemar Puszkarz, Apr 25 2016
STATUS
approved