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A071149 Numbers n such that the sum of the first n odd primes (A071148) is prime; analogous to A013916.

%I A071149 #29 Oct 08 2017 17:33:10
%S A071149 1,9,15,17,53,55,61,65,71,75,95,115,117,137,141,143,155,183,191,203,
%T A071149 249,273,275,283,291,305,339,341,377,409,411,415,435,439,449,483,495,
%U A071149 497,509,525,583,599,605,621,633,637,643,645,671,675,709,713,715,727
%N A071149 Numbers n such that the sum of the first n odd primes (A071148) is prime; analogous to A013916.
%H A071149 T. D. Noe, <a href="/A071149/b071149.txt">Table of n, a(n) for n = 1..1000</a>
%F A071149 a(n) = pi(A071150(n)). - _Charles R Greathouse IV_, May 13 2015
%p A071149 Primes:= select(isprime, [seq(2*i+1,i=1..10^4)]):
%p A071149 L:= ListTools:-PartialSums(Primes):
%p A071149 select(i -> isprime(L[i]), [$1..nops(L)]); # _Robert Israel_, May 19 2015
%t A071149 Position[Accumulate@ Prime@ Range[2, 750], _?(PrimeQ@# &)] // Flatten (* _Robert G. Wilson v_, May 19 2015, after _Harvey P. Dale_ in A013916 *)
%o A071149 (PARI) s=n=0; forprime(p=3,1e4, n++; if(isprime(s+=p), print1(n", "))) \\ _Charles R Greathouse IV_, May 13 2015
%Y A071149 Cf. A007504, A013916, A013917, A013918, A065091, A071148, A071150, A089228.
%K A071149 nonn
%O A071149 1,2
%A A071149 _Labos Elemer_, May 13 2002