A112856 - OEIS

%I #4 Aug 02 2022 13:28:26

%S 3,13,30241,670442572801,20007974164906320568399715106816000001,

%T 31370018474571622355156067715319586116075520000001

%N Primes of the form (2*n)!/n!+1.

%C Next term (2*72)!/72!+1 has 146 decimal digits.

%t Select[Table[(2n)!/n!+1,{n,50}],PrimeQ] (* _Harvey P. Dale_, Aug 02 2022 *)

%Y Cf. A112855 n such that (2*n)!/n!+1 is prime, A112854 primes of the form (2*n)!/n!-1.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Sep 25 2005