A322303 a(n) = Fibonacci(semiprime(n)).

3, 8, 34, 55, 377, 610, 10946, 17711, 75025, 121393, 3524578, 5702887, 9227465, 39088169, 63245986, 1836311903, 7778742049, 20365011074, 139583862445, 365435296162, 591286729879, 4052739537881, 17167680177565, 117669030460994, 1304969544928657, 5527939700884757

Offset

1,1

Links

Table of n, a(n) for n=1..26.

Maple

with(numtheory): with(combinat, fibonacci):
a:=proc(n) option remember; local h; if n=1 then 4; else for h from procname(n-1)+1 do if bigomega(h)=2 then return h; fi; od; fi; end:
seq(fibonacci(a(n)), n=1..30); # Muniru A Asiru, Dec 27 2018

Mathematica

Fibonacci[Select[Range[100], Plus@@Last/@FactorInteger[#]==2&]]
Fibonacci/@Select[Range[100], PrimeOmega[#]==2&] (* Harvey P. Dale, Feb 22 2024 *)

Prog

(Magma) [Fibonacci(n): n in [2..200] | &+[d[2]: d in Factorization(n)] eq 2];

Crossrefs

Cf. A000045 (Fibonacci), A001358 (semiprimes), A030426 (Fibonacci(primes)).

Sequence in context: A302629 A375249 A339315 * A117722 A231856 A024419

Adjacent sequences: A322300 A322301 A322302 * A322304 A322305 A322306

Keyword

nonn

Author

Vincenzo Librandi, Dec 26 2018

Status

approved