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A104466 a(n) is the least k with n distinct prime factors such that the sum of its prime factors (counting multiplicity) divides k, or 0 if no such k exists. First member of A036844 with n distinct prime factors. 1

%I #3 Mar 31 2012 13:20:57

%S 2,0,30,840,2730,72930,870870,9699690,340510170,9592993410,

%T 265257422430,8624101075590,304250263527210,14299762385778870,

%U 1164365758518632670,43657174563782890110,1987938667108592728530,172494415819766906755890

%N a(n) is the least k with n distinct prime factors such that the sum of its prime factors (counting multiplicity) divides k, or 0 if no such k exists. First member of A036844 with n distinct prime factors.

%C A001221(a(n)) = n; A001414(a(n)) divides a(n). a(4) = 840; A086487(4) = 1122. This is probably the only difference between these two sequences.

%e a(4) = 840 = 2^3*3*5*7; 2+2+2+3+5+7 = 21 divides 840.

%Y Cf. A001414, A001221, A086487, A104465.

%K nonn,less

%O 1,1

%A _David Wasserman_, Mar 09 2005

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Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)