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Sum of the first n safe primes.
1

%I #10 Aug 04 2023 23:16:45

%S 5,12,23,46,93,152,235,342,509,688,915,1178,1525,1884,2267,2734,3213,

%T 3716,4279,4866,5585,6424,7287,8174,9157,10176,11363,12646,13953,

%U 15272,16639,18078,19565,21088,22707,24530,26437,28464,30503,32566,34665

%N Sum of the first n safe primes.

%C The subsequence of prime partial sums of safe primes begins: 5, 23, 509, 2267, 9157, 26437. The subsubsequence of safe prime partial sums of safe primes begins: 5, 23, and then what values? Note that A172037 Prime partial sums of Sophie Germain primes A005384 is related because 2p+1 is called a safe prime if p is a Sophie Germain prime. - _Jonathan Vos Post_, Jan 30 2010

%t Accumulate[Select[Prime[Range[350]],PrimeQ[(#-1)/2]&]] (* _Harvey P. Dale_, Jul 27 2011 *)

%Y Cf. A005385.

%Y Cf. A172037. - _Jonathan Vos Post_, Jan 30 2010

%K easy,nonn

%O 1,1

%A _Joseph L. Pe_, Jan 21 2002