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%I #15 Aug 01 2015 06:04:25
%S 2,28,1060,39612,1336090,42157238,1271530648,37178373556,
%T 1062895088910,29878892909030,828999068943506,22762324818835316,
%U 619715756464336328,16753554900339748756,450233110894196298638
%N Sum of the first 5^n primes.
%C Using the program at the link, computation of the next term, a(15), would require generating a list of the first 31 * 10^9 8-byte primes (file size: 250 GB). Given runtimes of 0.06, 0.13, 0.63, 7.5, 64.6, 375.38, and 2092.56 seconds on a 2.53 GHz P4 processor for a(8) through a(14), respectively, the program in the link will sum the first 5^15 primes in 3.5 hours. [Comment reworded by _Jon E. Schoenfield_, Aug 01 2015]
%H C. Hilliard, <a href="http://groups.msn.com/First300billionprimes/sumfirst5nprimes.msnw">SumPrimes</a>. [broken link]
%F a(n) = A007504(A000351(n)). - _Michel Marcus_, Aug 01 2015
%e The first 5^1 primes add up to 28.
%t t = {}; c = 1; k = 3; s = 2; Do[ While[c < 5^n, If[PrimeQ[k], c++; s += k]; k += 2]; Print@s; AppendTo[t, s], {n, 0, 10}]; t (* _Robert G. Wilson v_, Jan 17 2006 *)
%K hard,nonn
%O 0,1
%A _Cino Hilliard_, Jan 15 2006
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