A098911 Table(n,2) read by rows giving k and j such that Mersenne-prime(k) - Mersenne-prime(j) - 1 is prime.

2, 1, 3, 2, 6, 2, 9, 6, 9, 7, 10, 9

Offset

1,1

Links

Table of n, a(n) for n=1..12.

Example

(2^3-1)-(2^2-1)-1 = 5 = Mersenne-prime(2)-Mersenne-prime(1)-1 k=2 j=1 for n=1
(2^5-1)-(2^3-1)-1 = 23 = Mersenne-prime(3)-Mersenne-prime(2)-1 k=3 j=2 for n=2
(2^17-1)-(2^3-1)-1 = 131063 = Mersenne-prime(6)-Mersenne-prime(2)-1 k=6 j=2 for n=3
and 3,23,131063 are primes

Crossrefs

Sequence in context: A319179 A114653 A069481 * A052305 A165045 A337452

Adjacent sequences: A098908 A098909 A098910 * A098912 A098913 A098914

Keyword

more,nonn,tabf

Author

Pierre CAMI, Oct 16 2004

Status

approved