a(n) = floor(n^n / 3^n).

Terms

a(0) =1a(1) =0a(2) =0a(3) =1a(4) =3a(5) =12a(6) =64a(7) =376a(8) =2557a(9) =19683a(10) =169350a(11) =1610592a(12) =16777216a(13) =189970982a(14) =2323244584a(15) =30517578125a(16) =428528437130