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%I #4 Mar 30 2012 18:51:26
%S 0,0,0,0,0,0,0,0,0,0,4,0,5,0,0,0,7,0,8,0,8,6,10,0,11,7,11,0,13,0,14,9,
%T 14,10,16,0,17,11,17,11,19,0,20,13,19,14,22,0,23,14,23,15,25,11,26,17,
%U 26,18,28,0,29,19,29,19,31,14,32,21,32,22,34,13,35,23,34,23,37,17,38
%N Largest base in which n is not divisible by any of its digits (0 if no such base).
%C If n is odd then a(n)<=(n-3)/2 since in base (n-1)/2 it is written 21, in bases (n+1)/2 through to n its first digit is 1 and in bases >n it is just itself as a single digit; and n is divisible by 1 and itself. If n is even then a(n)<=n/3 since in bases >n/3 through to n/2 its first digit is 2, in bases n/2+1 through to n its first digit is 1 and in bases >n it is just itself as a single digit; and n is divisible by 1, 2 and itself
%e a(11)=4 because it is written as 23 in base 4 and 11 is not divisible by 2 or 3; in every base from 5 through to 11 it has a digit 1 and in every base from 12 onwards it is simply digit 'eleven' - 11 is divisible by both 1 and 'eleven'
%Y Cf. A055238-A055242.
%K base,nonn
%O 1,11
%A _Henry Bottomley_, May 04 2000
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