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A087651 Sequence of primorials P# (cf. A002110) such that j*P# has twin prime neighbors for some j with 0 < j < prime following P. 3
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 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

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

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 (colettecami(AT)aol.com), Sep 28 2003

EXTENSIONS

Edited by Jud McCranie (judmccr(AT)bellsouth.net) and Ray Chandler (rayjchandler(AT)sbcglobal.net), Oct 05, 2003

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.