Number of +ve integers that have n as their greatest prime power

[Don Reble]

> %S A000001 1,1,2,2,6,0,12,8,16,0,48,0,96,0,0,48,240,0,480,0,0,0,960,0,960,0
> %T A000001 960,0,3840,0,7680,3072,0,0,0,0,18432,0,0,0,36864,0,73728,0,0,0
> %U A000001 147456,0,147456,0,0,0,442368,0,0,0,0,0,884736,0,1769472,0,0,589824
> %F A000001 a(1) = 1; a(p^k) = prod_{q <= p^k, q prime} { floor(k ln p / ln q) } / k when p prime, k >= 1, a(n) = 0 otherwise
> 
> Can someone confirm that the formula is correct, and perhaps check that
> my numbers are correct?

   The formula should have ceiling() instead of floor().
   The numbers are correct.
-- 
Don Reble  djr at nk.ca