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a(1) = 1; if n is composite then a(n) = Sum_{i < n, i not prime} a(i), else if n is prime then a(n) = sum_{ j < n, j is a noncomposite} a(j).
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%I #9 Dec 08 2015 02:41:48

%S 1,1,2,1,4,2,8,4,8,16,16,32,32,64,128,256,64,512,128,1024,2048,4096,

%T 256,8192,16384,32768,65536,131072,512,262144,1024,524288,1048576,

%U 2097152,4194304,8388608,2048,16777216,33554432,67108864,4096,134217728,8192

%N a(1) = 1; if n is composite then a(n) = Sum_{i < n, i not prime} a(i), else if n is prime then a(n) = sum_{ j < n, j is a noncomposite} a(j).

%F a(p(i)) = 2^(i-1); a(A002808(i)) = 2^(i-1). - _David Wasserman_, Jan 25 2005

%e a(7) = a(1) + a(2) + a(3) + a(5) = 8.

%Y Cf. A002033, A045545.

%K nonn

%O 1,3

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 02 2003

%E More terms from _David Wasserman_, Jan 25 2005