A088988 Least prime that begins a run of exactly 2n-1 primes between two consecutive prime-indexed primes.

7, 19, 89, 463, 809, 1223, 619, 15727, 3767, 6907, 9109, 14197, 22109, 27103, 41057, 55009, 10937, 99559, 357829, 216649, 177797, 172213, 1040813, 327779, 375043, 219937, 423019, 1049177, 536281, 523571, 402769, 1155431, 2192123, 1792103

Offset

1,1

Links

Table of n, a(n) for n=1..34.

Formula

a(n) = prime(1 + A000230(n)) = prime(1 + prime(A038664(n))).

Example

5 and 11 are the 3rd and 5th primes; 7 begins a run of 1 primes.
17 and 31 are the 7rd and 11th primes; 19 begins a run of 3 primes.

Prog

(PARI) pipprimes(n, m) = { for(x=1, n, c=0; p1 = prime(prime(x)); p2 = prime(prime(x+1)); forprime(y=p1+2, p2-2, c++); if(c==m, forprime(y=p1+2, p2-2, print1(y", "); ); ) ) }

Crossrefs

Sequence in context: A237436 A300556 A267378 * A109879 A109880 A363668

Adjacent sequences: A088985 A088986 A088987 * A088989 A088990 A088991

Keyword

nonn

Author

Cino Hilliard, Oct 31 2003

Extensions

Extended and edited by T. D. Noe, Apr 14 2009

Status

approved