A071195 Final prime in sequence of primes starting with prime(n) and having prime sum (see A071194), or -1 if no such sequence exists.

3, 29, 11, 13, 17, 29, 23, 29, 31, 37, 41, 71, 47, 61, 73, 61, 73, 71, 73, 79, 97, 89, 97, 113, 127, 107, 137, 131, 127, 139, 149, 173, 157, 151, 157, 173, 167, 173, 227, 223, 197, 293, 211, 239, 211, 251, 227, 239, 563, 239, 269, 397, 283, 409, 283, 281, 283

Offset

1,1

Comments

The length of the sequence is given in A071194.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Example

n=2: p(2)=3, 3+7+11+13+17+19+23+29 = 127 is the shortest partial sum with initial prime 3; it ends with p(10) = 29 = a(2);
n=6: p(6)=13, 13+17+19+23+29 = 101, so the end-prime = a(6) = 29.

Mathematica

Prime@ Table[k = 1; While[! PrimeQ@ Total@ Prime@ Range[n, n + k], k++]; n + k, {n, 57}] (* Michael De Vlieger, Mar 25 2017 *)

Prog

(PARI) a(n, p=prime(n))=my(q=p); while(!isprime(p+=q=nextprime(q+1)), ); q
apply(p->a(0, p), primes(30)) \\ Charles R Greathouse IV, Jun 16 2015

Crossrefs

Cf. A071194, A071196, A071197, A071198.

Sequence in context: A096621 A362466 A143234 * A292625 A030274 A249518

Adjacent sequences: A071192 A071193 A071194 * A071196 A071197 A071198

Keyword

nonn

Author

Labos Elemer, May 16 2002

Extensions

Edited and escape clause added by N. J. A. Sloane, Nov 17 2020

Status

approved