OFFSET
1,1
COMMENTS
The next term has 595 digits. - Harvey P. Dale, May 30 2016
EXAMPLE
a(2) = 3! + 4! + 1 = 6 + 24 + 1 = 31.
a(3) = 7! + 8! + 1 = 5040 + 40320 + 1 = 45361.
MAPLE
P:=proc(n) local i, j; for i from 1 by 1 to n do j:=i!+(i+1)!+1; if isprime(j) then print(j); fi; od; end: P(200);
MATHEMATICA
lst={}; Do[p=n!+(n+1)!+1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 27 2009 *)
Select[Total[#]+1&/@Partition[Range[0, 300]!, 2, 1], PrimeQ] (* Harvey P. Dale, May 30 2016 *)
PROG
(PARI) for(n=0, 1e3, if(isprime(k=n!+(n+1)!+1), print1(k", "))) \\ Charles R Greathouse IV, Feb 14 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava and Giorgio Balzarotti, May 25 2006
EXTENSIONS
First term inserted (because 0! + 1! + 1 = 3 is prime) by Dmitry Kamenetsky, Oct 21 2008
STATUS
approved