List of pairs: first pair is (1,1); then follow (x,y) with (x+2y, x+y).

Terms

a(0) =1a(1) =1a(2) =3a(3) =2a(4) =7a(5) =5a(6) =17a(7) =12a(8) =41a(9) =29a(10) =99a(11) =70a(12) =239a(13) =169a(14) =577a(15) =408a(16) =1393a(17) =985a(18) =3363a(19) =2378a(20) =8119a(21) =5741a(22) =19601a(23) =13860a(24) =47321a(25) =33461a(26) =114243a(27) =80782a(28) =275807a(29) =195025