a(n) = smallest number with shortest addition chain of length n.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =7a(5) =11a(6) =19a(7) =29a(8) =47a(9) =71a(10) =127a(11) =191a(12) =379a(13) =607a(14) =1087a(15) =1903a(16) =3583a(17) =6271a(18) =11231a(19) =18287a(20) =34303a(21) =65131a(22) =110591a(23) =196591a(24) =357887a(25) =685951a(26) =1176431a(27) =2211837a(28) =4169527a(29) =7624319