A071149 Numbers n such that the sum of the first n odd primes (A071148) is prime; analogous to A013916.

1, 9, 15, 17, 53, 55, 61, 65, 71, 75, 95, 115, 117, 137, 141, 143, 155, 183, 191, 203, 249, 273, 275, 283, 291, 305, 339, 341, 377, 409, 411, 415, 435, 439, 449, 483, 495, 497, 509, 525, 583, 599, 605, 621, 633, 637, 643, 645, 671, 675, 709, 713, 715, 727

Offset

1,2

Links

T. D. Noe, Table of n, a(n) for n = 1..1000

Formula

a(n) = pi(A071150(n)). - Charles R Greathouse IV, May 13 2015

Maple

Primes:= select(isprime, [seq(2*i+1, i=1..10^4)]):
L:= ListTools:-PartialSums(Primes):
select(i -> isprime(L[i]), [$1..nops(L)]); # Robert Israel, May 19 2015

Mathematica

Position[Accumulate@ Prime@ Range[2, 750], _?(PrimeQ@# &)] // Flatten (* Robert G. Wilson v, May 19 2015, after Harvey P. Dale in A013916 *)

Prog

(PARI) s=n=0; forprime(p=3, 1e4, n++; if(isprime(s+=p), print1(n", "))) \\ Charles R Greathouse IV, May 13 2015

Crossrefs

Cf. A007504, A013916, A013917, A013918, A065091, A071148, A071150, A089228.

Sequence in context: A363896 A061838 A037002 * A289689 A316752 A358725

Adjacent sequences: A071146 A071147 A071148 * A071150 A071151 A071152

Keyword

nonn

Author

Labos Elemer, May 13 2002

Status

approved