%I #44 Aug 13 2024 21:02:41
%S 0,0,0,1,2,3,4,6,8,11,16,24,34,51,74,111,166,251,376,574,871,1329,
%T 2033,3121,4794,7396,11425,17688,27426,42613,66317,103298,161207,
%U 251757,393790,616645,966507,1516410,2381429,3743010,5888201,9269519,14604028
%N Number of primes <= the n-th Fibonacci number.
%H David Baugh, <a href="/A054782/b054782.txt">Table of n, a(n) for n = 0..123</a> (terms n = 0..70 from H. J. Smith, terms n = 71..123 found using Kim Walisch's primecount program)
%F a(n) = pi(F(n)) = A000720(A000045(n)). - _Vincenzo Librandi_, Apr 25 2019
%p with(combinat): with(numtheory): seq(pi(fibonacci(n)), n = 0 .. 42); # _Emeric Deutsch_, Jun 24 2009
%t Table[PrimePi[Fibonacci[n]], {n, 0, 50}] (* _Vincenzo Librandi_, Apr 25 2019 *)
%o (Sage) [prime_pi(fibonacci(n)) for n in range(0, 43)] # _Zerinvary Lajos_, Jun 06 2009
%o (Magma) [0] cat [#PrimesUpTo(Fibonacci(n)): n in [1..42]]; // _Vincenzo Librandi_, Apr 25 2019
%o (PARI) a(n) = primepi(fibonacci(n)); \\ _Michel Marcus_, Apr 25 2019
%Y Cf. A000045, A000720.
%K nonn,changed
%O 0,5
%A _Jeff Burch_, May 22 2000
%E More terms from _James A. Sellers_, May 23 2000; and _N. J. A. Sloane_, Nov 07 2000.
%E Four more terms from _Rick L. Shepherd_, Dec 06 2004
%E Three more terms a(40), a(41), a(42) from _Harry J. Smith_, Dec 16 2008
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