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Begin with the n-th composite number (A002808(n)) and go on adding successive composite numbers; a(n) is the first prime that arises as the sum.
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%I #9 Dec 05 2013 19:56:48

%S 37,23,17,19,67,41,29,31,97,59,41,43,71,983,383,53,293,157,277,373,67,

%T 353,71,113,653,79,467,131,89,139,193,97,311,101,103,919,109,743,113,

%U 563,307,587,457,127,263,131,419,137,139,367,613,149,151,311,653,239

%N Begin with the n-th composite number (A002808(n)) and go on adding successive composite numbers; a(n) is the first prime that arises as the sum.

%e a(5) = 10+12+14+15+16 because 10+12, 10+12+14 and 10+12+14+15 are composite, but 10+12+14+15+16 is prime.

%t Rest[With[{cnos=Select[Range[100],!PrimeQ[#]&]},Table[First[Select[ Accumulate[Drop[cnos,n-1]],PrimeQ]],{n,60}]]] (* _Harvey P. Dale_, Aug 24 2011 *)

%Y Cf. A073686.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Apr 19 2004

%E More terms from _David Wasserman_, Apr 20 2007