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A113633
Sum of the first 5^n primes.
3
2, 28, 1060, 39612, 1336090, 42157238, 1271530648, 37178373556, 1062895088910, 29878892909030, 828999068943506, 22762324818835316, 619715756464336328, 16753554900339748756, 450233110894196298638, 12038074430656287496566, 320451759639384414082274, 8497567719126134980044214
OFFSET
0,1
COMMENTS
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]
LINKS
Amiram Eldar, Table of n, a(n) for n = 0..24 (calculated using Kim Walisch's primesum program)
Cino Hilliard, SumPrimes. [broken link]
FORMULA
a(n) = A007504(A000351(n)). - Michel Marcus, Aug 01 2015
EXAMPLE
The first 5^1 primes add up to 28.
MATHEMATICA
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 *)
KEYWORD
nonn
AUTHOR
Cino Hilliard, Jan 15 2006
EXTENSIONS
a(15) onwards from Amiram Eldar, Jul 01 2024
STATUS
approved