A222255 - OEIS

%I #8 Mar 28 2013 04:33:11

%S 2,2,2,2,5,5,193,2903041,250822656001,1807729046323200001,

%T 1472038679443987759104000001,

%U 21817028147643299474152432146548259236610048000000000001

%N Primes of the form n!/n# + 1, where n#=A034386(n) (primorial), listed with repetition.

%C For each n >= 0, if n!/n#+1 is prime, then this prime is listed here: This explains the repetitions.

%C The next term is already 126 digits long.

%F a(n) = A049614(A140294(n))+1, where A049614 = A000142/A034386.

%o (PARI) for(n=0,99,ispseudoprime(a=n!/prod(k=1,primepi(n),prime(k))+1)&print1(a","))

%K nonn

%O 1,1

%A _M. F. Hasler_, Mar 27 2013