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a(n) = sum of distinct prime divisors of 2*prime(n)-1.
0

%I #9 Dec 29 2014 03:24:44

%S 3,5,3,13,10,5,14,37,8,22,61,73,3,22,34,15,16,11,26,50,34,157,19,62,

%T 193,70,46,74,38,8,34,32,23,277,14,50,313,18,40,31,27,19,130,23,134,

%U 397,421,94,154,457,39,56,50,170,22,15,182,541,86,31,118,21,613,26

%N a(n) = sum of distinct prime divisors of 2*prime(n)-1.

%t Array[Plus@@First/@FactorInteger[2*Prime[ # ]-1]&,5! ] (* _Vladimir Joseph Stephan Orlovsky_, Feb 28 2010 *)

%K nonn

%O 1,1

%A _Clark Kimberling_