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A101207 For each prime power n, a(n) is the number of positive integers that have n as their greatest prime power.

%I A101207 #9 Jun 25 2022 20:02:16
%S A101207 1,1,2,2,6,0,12,8,16,0,48,0,96,0,0,48,240,0,480,0,0,0,960,0,960,0,960,
%T A101207 0,3840,0,7680,3072,0,0,0,0,18432,0,0,0,36864,0,73728,0,0,0,147456,0,
%U A101207 147456,0,0,0,442368,0,0,0,0,0,884736,0,1769472,0,0,589824
%N A101207 For each prime power n, a(n) is the number of positive integers that have n as their greatest prime power.
%C A101207 a(n) is the number of occurrences of n in A034699.
%F A101207 a(1) = 1; a(p^k) = prod_{q <= p^k, q prime} { ceiling(k log p / log q) } / k when p prime, k >= 1, a(n) = 0 otherwise
%e A101207 a(4) = 2 since only 4 and 12 have 4 as their greatest prime power - all other multiples of 4 are divisible by 8, 9, or some prime >= 5.
%Y A101207 Cf. A034699.
%K A101207 nonn,easy
%O A101207 1,3
%A A101207 _Hugo van der Sanden_, Dec 13 2004