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Fibonacci numbers whose decimal expansion does not contain any digit 3.
5

%I #14 Sep 08 2022 08:45:53

%S 0,1,2,5,8,21,55,89,144,610,987,1597,2584,4181,6765,10946,17711,28657,

%T 75025,196418,514229,5702887,9227465,24157817,165580141,267914296,

%U 4807526976,7778742049,12586269025,86267571272,591286729879,956722026041,1548008755920

%N Fibonacci numbers whose decimal expansion does not contain any digit 3.

%C Probability that Fib(n) contains no 3's decreases to zero as n goes to infinity. I suppose that the maximum number is Fib(223) having 47 digits, none of them being a "3".

%e a(6)=21 since 21 is the 6th Fibonacci having no 3's.

%t Join[{0}, Select[Fibonacci[Range[2, 60]], DigitCount[#, 10, 3]==0&]] (* _Vincenzo Librandi_, May 09 2019 *)

%o (Magma) [0] cat [Fibonacci(n): n in [2..150] | not 3 in Intseq(Fibonacci(n))]; // _Vincenzo Librandi_, May 09 2019

%Y Cf. A000045, A177194, A177195, A177231, A176253

%K nonn,base

%O 1,3

%A _Carmine Suriano_, May 06 2010

%E a(1) changed from 1 to 0 by _Vincenzo Librandi_, May 09 2019