%I #15 Sep 16 2016 15:14:31
%S 0,1,1,2,3,5,8,31,21,43,55,98,441,332,773,610,987,9751,8542,8411,7665,
%T 96410,77111,87652,86643,75520,933211,986411,873111,954221,843200,
%U 9664321,9873210,8755432,8877520,9765422,95433210,87754211,99886310,98665432
%N Arrange the base 10 digits of the n-th Fibonacci number in descending order.
%C Conjecture: the largest Fibonacci number F(n) with its base 10 digits already sorted in descending order is F(16) = 987.
%F a(n) = A004186(A000045(n)). - _Michel Marcus_, May 15 2016
%e a(7) = 31 because F(7) = 13, so the digits in descending order become 31.
%e a(8) = 21 = F(8), the digits are already in descending order.
%t FromDigits[Reverse[Sort[IntegerDigits[#]]]]&/@Fibonacci[Range[0,50]] (* _Harvey P. Dale_, Sep 16 2016 *)
%o (PARI) a(n)=fromdigits(vecsort(digits(fibonacci(n)),,4)) \\ _Charles R Greathouse IV_, May 15 2016
%Y Cf. A000045, A004186, A272918, A273046.
%K nonn,base,easy
%O 0,4
%A _Alonso del Arte_, May 12 2016
%E Corrected and extended by _Harvey P. Dale_, Sep 16 2016