A182693 - OEIS

%I #8 Mar 30 2012 19:00:24

%S 0,101,121,106,625,116,729,102,100,112,0,108,0,192,144,120,0,180,0,

%T 240,576,0,0,360,0,0,900,960,0,720,0,840,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

%U 0,0,0,0,0,0,0

%N a(n) = the smallest 3-digit number with exactly n divisors, a(n) = 0 if no such number exists.

%C max {n : a(n) > 0} = 32, a(n) = 0 for n > 32.

%F a(n) = min {99 < k < 1000 : A000005(k)=n} if set is nonempty, else a(n) = 0.

%p with (numtheory):

%p b:= n-> `if` (type (n, integer), n, 0):

%p a:= n-> b (min (select (x-> tau(x)=n, [$100..999])[])):

%p seq (a(n), n=1..60);

%Y Cf. A000005, A182694.

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Nov 27 2010

%E Edited by _Alois P. Heinz_, Nov 27 2010