A Pascal-like triangle based on 3^n.

Terms

a(0) =1a(1) =3a(2) =1a(3) =9a(4) =4a(5) =1a(6) =27a(7) =13a(8) =5a(9) =1a(10) =81a(11) =40a(12) =18a(13) =6a(14) =1a(15) =243a(16) =121a(17) =58a(18) =24a(19) =7a(20) =1a(21) =729a(22) =364a(23) =179a(24) =82a(25) =31a(26) =8a(27) =1a(28) =2187a(29) =1093