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A215780 Primes of the form 2*n!!-1. 1
3, 5, 29, 1889, 20789, 270269, 15811707161249, 443286190953399543749, 433724868863888852244234239999, 163685683629861106170483229851647999999, 10144121732653119949813597183199268946575359999999, 67476497990875549413061344119283906281177486718749 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The corresponding n are in A215779.

LINKS

Table of n, a(n) for n=0..11.

EXAMPLE

31 =  2*5!!+1 = 2*15 +1 is in the sequence.

MATHEMATICA

a={}; Do[p= 2*n!! -1; If[PrimeQ[p], AppendTo[a, p]], {n, 0, 800}]; Print[a];

CROSSREFS

Cf. A006882, A215779.

Sequence in context: A100857 A100856 A100858 * A214655 A181429 A162262

Adjacent sequences:  A215777 A215778 A215779 * A215781 A215782 A215783

KEYWORD

nonn

AUTHOR

Michel Lagneau, Aug 23 2012

STATUS

approved

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Last modified September 21 12:13 EDT 2020. Contains 337271 sequences. (Running on oeis4.)