Sum of the degrees of asymmetry of all ternary words of length n.

Terms

a(0) =0a(1) =0a(2) =6a(3) =18a(4) =108a(5) =324a(6) =1458a(7) =4374a(8) =17496a(9) =52488a(10) =196830a(11) =590490a(12) =2125764a(13) =6377292a(14) =22320522a(15) =66961566a(16) =229582512a(17) =688747536a(18) =2324522934a(19) =6973568802a(20) =23245229340a(21) =69735688020a(22) =230127770466a(23) =690383311398