A143384 Duplicate of A139426.

1, 5, 1, 5, 11, 11, 17, 19, 23, 97, 127, 145, 167, 269, 767, 479, 3307, 1453, 18007, 2357, 599, 17669, 5527, 3191, 3251, 70249, 147773, 39637

Offset

1,2

Comments

All primes certified using PFGW from Primeform group.

Links

Table of n, a(n) for n=1..28.

Example

(2^2-1)*(2^2-1+1)-1=11 prime 2^2-1=M(1) so a(1)=1
(2^3-1)*(2^3-1+1)-1=55 composite
(2^3-1)*(2^3-1+3)-1=69 composite
(2^3-1)*(2^3-1+5)-1=83 prime 2^3-1=M(2) so a(2)=5

Crossrefs

Cf. A000043 (Mersenne prime exponents), A143385.

Sequence in context: A255166 A131113 A139426 * A046611 A145825 A101692

Adjacent sequences: A143381 A143382 A143383 * A143385 A143386 A143387

Keyword

dead

Author

Pierre CAMI, Aug 11 2008

Extensions

Missing terms 2357 and 599 inserted by Jens Kruse Andersen, Jul 30 2014

Status

approved