A086167 a(n) = sum of the first n lower twin primes.

3, 8, 19, 36, 65, 106, 165, 236, 337, 444, 581, 730, 909, 1100, 1297, 1524, 1763, 2032, 2313, 2624, 2971, 3390, 3821, 4282, 4803, 5372, 5971, 6588, 7229, 7888, 8697, 9518, 10345, 11202, 12083, 13102, 14133, 15182, 16243, 17334, 18485

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

For n = 4 we have twin prime pairs (3,5) (5,7) (11,13) (17,19) and 3 + 5 + 11 + 17 = 36.

Mathematica

lst = {}; s = 0; Do[p = Prime[n]; If[PrimeQ[p + 2], s += p; AppendTo[lst,  s]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 30 2008 *)
Accumulate[Transpose[Select[Partition[Prime[Range[200]], 2, 1], #[[2]] - #[[1]] == 2 &]][[1]]] (* Harvey P. Dale, Feb 02 2011 *)

Prog

(PARI) addnexttwin(n)= { s=0; for(x=1, n, if(prime(x+1)-prime(x)==2, s=s+prime(x); print1(s", ")) ) }

Crossrefs

Cf. A001359, A086168.

Sequence in context: A139020 A147358 A209367 * A083186 A055341 A067332

Adjacent sequences: A086164 A086165 A086166 * A086168 A086169 A086170

Keyword

nonn

Author

Cino Hilliard, Aug 25 2003

Status

approved