Number of ternary sequences with primitive period n.

Terms

a(0) =1a(1) =3a(2) =6a(3) =24a(4) =72a(5) =240a(6) =696a(7) =2184a(8) =6480a(9) =19656a(10) =58800a(11) =177144a(12) =530640a(13) =1594320a(14) =4780776a(15) =14348640a(16) =43040160a(17) =129140160a(18) =387400104a(19) =1162261464a(20) =3486725280a(21) =10460350992a(22) =31380882456a(23) =94143178824a(24) =282428998560a(25) =847288609200