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Sphenic Fibonacci numbers.
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%I #16 Oct 04 2021 08:11:36

%S 610,987,10946,3524578,9227465,24157817,39088169,63245986,1836311903,

%T 7778742049,20365011074,591286729879,4052739537881,17167680177565,

%U 44945570212853,61305790721611591,420196140727489673,1500520536206896083277,6356306993006846248183

%N Sphenic Fibonacci numbers.

%C Intersection of A000045 and A007304. There are 28 sphenic numbers among the first 200 positive Fibonacci numbers.

%F A000045 INTERSECT A007304.

%e 610 is a term since it is a Fibonacci number that is a product of 3 distinct primes, 610=2*5*61, which makes it a sphenic number.

%t Select[Fibonacci@Range[120], SquareFreeQ[#]&&PrimeNu[#]==3&]

%o (PARI) for(n=1, 120, fn=fibonacci(n); issquarefree(fn)&&omega(fn)==3&&print1(fn ","))

%Y Cf. A000045, A007304, A061305 (squarefree Fibonaccis), A137563 (Fibonaccis with 3 distinct primes).

%K nonn

%O 1,1

%A _Waldemar Puszkarz_, Mar 23 2018