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A122724 Primes p such that (2p)! - 1 is also prime. 0
2, 3, 7, 19, 47, 83, 487 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Corresponding primes of the form (2p)! - 1 are {23,719,87178291199,523022617466601111760007224100074291199999999,...}.

No other terms < 20663. - Robert Price, Mar 02 2012

LINKS

Table of n, a(n) for n=1..7.

CROSSREFS

Cf. A002982, A103317.

Sequence in context: A069051 A229290 A246033 * A256758 A033844 A037028

Adjacent sequences:  A122721 A122722 A122723 * A122725 A122726 A122727

KEYWORD

hard,more,nonn

AUTHOR

Alexander Adamchuk, Sep 23 2006

STATUS

approved

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Last modified August 20 01:14 EDT 2019. Contains 326136 sequences. (Running on oeis4.)