A239683 - OEIS

%I #27 Apr 04 2014 13:26:27

%S 1,1,2,3,4,4,4,5,5,5,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,

%T 8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,10,10,10,

%U 10,10,10,10,10,10,10,10,10,10,10,10,10,10

%N Number of digits in decimal expansion of n^5.

%F a(n) = A055642(n^5).

%F a(n) = k log n + O(1) where k = 2.1714... = 5/log 10. - _Charles R Greathouse IV_, Apr 01 2014

%e a(1) = 1 because 1^5 = 1, which has only 1 digit.

%e a(5) = 4 because 5^5 = 3125, which has 4 digits.

%o (PARI) vector(110,n,#digits(n^5)) \\ _Joerg Arndt_, Mar 24 2014

%Y Cf. A000584.

%K nonn,base,easy

%O 0,3

%A _Lorianne Kwak_, Mar 24 2014