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Sum of primes < 2^n.
10

%I #20 Mar 24 2018 05:57:55

%S 0,5,17,41,160,501,1720,6081,22548,80189,289176,1070091,3908641,

%T 14584641,54056763,202288087,761593692,2867816043,10862883985,

%U 41162256126,156592635694,596946687124,2280311678414,8729068693022

%N Sum of primes < 2^n.

%H Kim Walisch, <a href="/A130739/b130739.txt">Table of n, a(n) for n = 1..80</a> (terms n=1..42 from Cino Hilliard)

%H Kim Walisch, <a href="https://github.com/kimwalisch/primesum">primesum program</a>.

%F a(n) = Sum_{i=2..2^n-1} A061397(i).

%e a(3) is 17 because the sum of primes less than 2^3 is 2+3+5+7=17.

%t Table[Sum[Prime[i], {i, PrimePi[2^n-1]}], {n, 1, 10}]

%o (PARI) a(n) = {s = 0; forprime(p=2, 2^n-1, s +=p); return (s);} \\ _Michel Marcus_, Jul 17 2013

%Y Cf. A046731, A099824.

%K nonn

%O 1,2

%A _Graeme McRae_, Jul 06 2007