Largest prime substring in n! (0 if none).

Terms

a(0) =0a(1) =0a(2) =2a(3) =0a(4) =2a(5) =2a(6) =7a(7) =5a(8) =3a(9) =3a(10) =3a(11) =991a(12) =9001a(13) =227a(14) =8291a(15) =1307a(16) =209227a(17) =68742809a(18) =4023737a(19) =164510040883a(20) =24329020081a(21) =510909421717a(22) =1240007a(24) =4840173323