OFFSET
1,1
COMMENTS
The corresponding k are in A215779.
EXAMPLE
29 = 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];
Select[2 Range[70]!!-1, PrimeQ] (* Harvey P. Dale, Dec 31 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Aug 23 2012
EXTENSIONS
Offset changed to 1 by Jinyuan Wang, May 15 2021
STATUS
approved