a(n) = binomial(prime(3+n), prime(3)).

Terms

a(0) =1a(1) =21a(2) =462a(3) =1287a(4) =6188a(5) =11628a(6) =33649a(7) =118755a(8) =169911a(9) =435897a(10) =749398a(11) =962598a(12) =1533939a(13) =2869685a(14) =5006386a(15) =5949147a(16) =9657648a(17) =13019909a(18) =15020334a(19) =22537515a(20) =29034396a(21) =41507642a(22) =64446024a(23) =79208745a(24) =87541245a(25) =106308566a(26) =116828271a(27) =140364532a(28) =254231775