a(0)=2, a(1)=3, a(2)=5, a(n) = smallest prime greater than or equal to a(n-1) + a(n-2) + a(n-3).

Terms

a(0) =2a(1) =3a(2) =5a(3) =11a(4) =19a(5) =37a(6) =67a(7) =127a(8) =233a(9) =431a(10) =797a(11) =1471a(12) =2699a(13) =4967a(14) =9137a(15) =16811a(16) =30931a(17) =56891a(18) =104639a(19) =192461a(20) =354001a(21) =651103a(22) =1197571a(23) =2202677a(24) =4051361a(25) =7451617a(26) =13705667a(27) =25208653a(28) =46365959a(29) =85280323