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%I #9 Nov 12 2020 06:43:21
%S 2,5,73,167,2423,7621,39233,50969,89563,198139,207029,267143,322963,
%T 335117,438517,481207,541547,812051,874697,917611,939293,1077761,
%U 1149593,1354267,1464011,1695559,1880401,2510083,2548703,3115249,3157487,3505849,4519057
%N Prime partial sums of Sophie Germain primes A005384.
%C a(1) and a(2) are themselves Sophie Germain primes.
%H Nathaniel Johnston, <a href="/A172037/b172037.txt">Table of n, a(n) for n = 1..1000</a>
%F A000040 INTERSECTION A066819 = {p such that p is prime and SUM[i=1..k]A005384(k) is prime} = {p such that p is prime and SUM[i=1..k]{p is prime and 2p+1 is prime}.}.
%e a(1) = 2 = first Sophie Germain prime A005384(1). a(2) = 5 = sum of first two Sophie Germain primes = 2+3. a(3) = 73 = sum of first six Sophie Germain primes = 2+3+5+11+23+29.
%t Select[Accumulate[Select[Prime[Range[5000]],PrimeQ[2#+1]&]],PrimeQ] (* _Harvey P. Dale_, Nov 27 2013 *)
%Y Cf. A000040, A005384, A005385, A066819, A172036.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Jan 23 2010
%E a(7) - a(34) from _Nathaniel Johnston_, Apr 29 2011
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