A112856 Primes of the form (2*n)!/n!+1.

3, 13, 30241, 670442572801, 20007974164906320568399715106816000001, 31370018474571622355156067715319586116075520000001

Offset

1,1

Comments

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

Links

Table of n, a(n) for n=1..6.

Mathematica

Select[Table[(2n)!/n!+1, {n, 50}], PrimeQ] (* Harvey P. Dale, Aug 02 2022 *)

Crossrefs

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

Sequence in context: A087333 A320041 A016104 * A007523 A092830 A317481

Adjacent sequences: A112853 A112854 A112855 * A112857 A112858 A112859

Keyword

nonn

Author

Hugo Pfoertner, Sep 25 2005

Status

approved