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A062698
Primes of form 2n! + 1.
1
3, 5, 13, 241, 958003201, 12804747411456001, 20666295932772289859333302675046400000001, 3102237506574764560448486032938606422126519440033972224000000000001, 8549766568120051128596027506778799299380687576733627449344000000000001
OFFSET
1,1
LINKS
MATHEMATICA
lst={}; Do[p=2*n!+1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 28 2009 *)
Select[2*Range[200]!+1, PrimeQ] (* Harvey P. Dale, Oct 26 2013 *)
PROG
(PARI) for(n=1, 55, if(isprime(2*n!+1), print(2*n!+1)))
(PARI) { n=0; f=1; for (m=1, 10^5, f*=m; if(isprime(a=2*f + 1), write("b062698.txt", n++, " ", a); if (n==12, break)) ) } \\ Harry J. Smith, Aug 09 2009
CROSSREFS
Sequence in context: A123370 A110407 A340037 * A200769 A128341 A177007
KEYWORD
nonn
AUTHOR
Jason Earls, Jul 10 2001
EXTENSIONS
One additional term from Harvey P. Dale, Oct 26 2013
STATUS
approved