A073837 Sum of primes p satisfying n <= p <= 2n.

2, 5, 8, 12, 12, 18, 31, 24, 41, 60, 60, 72, 72, 59, 88, 119, 119, 102, 139, 120, 161, 204, 204, 228, 228, 228, 281, 281, 281, 311, 372, 341, 341, 408, 408, 479, 552, 515, 515, 594, 594, 636, 636, 593, 682, 682, 682, 635, 732, 732, 833, 936, 936, 990, 1099, 1099

Offset: 1

Author

Amarnath Murthy, Aug 12 2002

Keywords

• nonn

Comments

a(n) = A034387(2*n) - A034387(n-1); a(n) <= A179213(n). [Reinhard Zumkeller, Jul 05 2010]

Examples

			a(7) = 31 = 7+11+13 (sum of primes between 7 and 14).
		

Links

• T. D. Noe, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A073838.

Programs

Maple

for n from 1 to 150 do l := 0:for j from n to 2*n do if isprime(j) then l := l+j:fi:od:a[n] := l:od:seq(a[j],j=1..150);

Mathematica

Table[Total[Select[Range[n, 2 n], PrimeQ]], {n, 56}] (* Jayanta Basu, Aug 12 2013 *)

PARI

a(n)=sum(i=n,2*n,i*isprime(i))

Extensions

More terms from Sascha Kurz and Benoit Cloitre, Aug 14 2002