A087651 Sequence of primorials P# (cf. A002110) such that j*P# has twin prime neighbors for some j with 0 < j < prime following P.

2, 6, 6, 6, 30, 30, 30, 30, 210, 210, 2310, 2310, 2310, 2310, 30030, 30030, 30030, 30030, 30030, 30030, 510510, 510510, 9699690, 223092870, 223092870, 223092870, 223092870, 223092870, 223092870, 223092870, 6469693230, 200560490130

Offset

0,1

Comments

I think I have found a proof that the sequence is infinite.

Links

Table of n, a(n) for n=0..31.

Example

I have found the first 122 values of this sequence, 121 and 122 are 2557#, 2557# with j=303 and j=2307, 1087 and 1088 digits.

Crossrefs

The j values are in A087730, P values are in A087731, i values are in A088676.

Cf. A002110, A086916, A087732.

Smaller of twin primes are in A087732. Number of digits in twin primes are in A086916.

Sequence in context: A161331 A120627 A089879 * A078579 A110936 A197850

Adjacent sequences: A087648 A087649 A087650 * A087652 A087653 A087654

Keyword

nonn

Author

Pierre CAMI, Sep 28 2003

Extensions

Edited by Jud McCranie and Ray Chandler, Oct 05 2003

Status

approved