Smallest prime factor of n!-1 (for n>2), a(2)=1.

Terms

a(0) =1a(1) =5a(2) =23a(3) =7a(4) =719a(5) =5039a(6) =23a(7) =11a(8) =29a(9) =13a(10) =479001599a(11) =1733a(12) =87178291199a(13) =17a(14) =3041a(15) =19a(16) =59a(17) =653a(18) =124769a(19) =23a(20) =109a(21) =51871a(22) =625793187653a(23) =149a(24) =20431a(25) =29a(26) =239a(27) =31a(29) =787