a(n) = phi( a(n-1) + a(n-2) + 1) with a(0) = 0 and a(1) = 1.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =2a(5) =4a(6) =6a(7) =10a(8) =16a(9) =18a(10) =24a(11) =42a(12) =66a(13) =108a(14) =120a(15) =228a(16) =348a(17) =576a(18) =720a(19) =1296a(20) =2016a(21) =3312a(22) =5256a(23) =7200a(24) =12456a(25) =17860a(26) =25200a(27) =40256a(28) =37368a(29) =39600