A214045 - OEIS

%I #7 May 14 2019 16:34:57

%S 1,1,2,2,3,5,6,7,8,10,11,13,15,16,18,20,21,23,25,27,29,31,33,35,37,39,

%T 41,43,45,47,49,51,53,56,58,60,62,64,67,69,71,74,76,78,81,83,86,88,90,

%U 93,95,98,100,103,105,108,110,113,115

%N Least m>0 such that n! <= 5^m.

%H Clark Kimberling, <a href="/A214045/b214045.txt">Table of n, a(n) for n = 1..1000</a>

%e a(6) = 5 because 5^4 < 6! <= 5^5.

%t Table[m=1; While[n!>5^m, m++]; m, {n,1,100}]

%t Join[{1},Table[Ceiling[Log[5,n!]],{n,2,90}]] (* _Harvey P. Dale_, May 14 2019 *)

%Y Cf. A213858.

%K nonn,easy

%O 1,3

%A _Clark Kimberling_, Jul 18 2012