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a(n) = A184728(n)/A130533(n) unless A130533(n) = 0 in which case a(n) = 0.
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%I #5 Mar 30 2012 17:25:56

%S 0,0,4,1,1,1,10,1,12,1,16,11,8,1,4,1,1,1,1,28,9,1,1,8,1,12,1,42,17,1,

%T 1,46,31,7,1,1,28,39,39,60,11,13,25,66,1,70,47,47,72,1,38,1,1,26,1,7,

%U 88,1,1,61,20,17,100,67,67,102,29,41,106

%N a(n) = A184728(n)/A130533(n) unless A130533(n) = 0 in which case a(n) = 0.

%C a(n) is the "level" of semiprimes.

%C The decomposition of semiprimes into weight * level + gap is A001358(n) = A130533(n) * a(n) + A065516(n) if a(n) > 0.

%C A184728(n) = A001358(n) - A065516(n) if A001358(n) - A065516(n) > A065516(n), 0 otherwise.

%H Rémi Eismann, <a href="/A184729/b184729.txt">Table of n, a(n) for n = 1..10000</a>

%e For n = 1 we have A130533(1) = 0, hence a(1) = 0.

%e For n = 3 we have A184728(3)/A130533(3)= 8 / 2 = 4; hence a(3) = 4.

%e For n = 20 we have A184728(20)/A130533(20)= 56 / 2 = 28; hence a(20) = 28.

%Y Cf. A001358, A065516, A130533, A184728, A117078, A117563, A001223, A118534.

%K nonn

%O 1,3

%A _Rémi Eismann_, Jan 20 2011