The (1,2)-Pascal triangle (or Lucas triangle) read by rows.

Terms

a(0) =2a(1) =1a(2) =2a(3) =1a(4) =3a(5) =2a(6) =1a(7) =4a(8) =5a(9) =2a(10) =1a(11) =5a(12) =9a(13) =7a(14) =2a(15) =1a(16) =6a(17) =14a(18) =16a(19) =9a(20) =2a(21) =1a(22) =7a(23) =20a(24) =30a(25) =25a(26) =11a(27) =2a(28) =1a(29) =8