A001045(n)^3.

Terms

a(0) =1a(1) =27a(2) =125a(3) =1331a(4) =9261a(5) =79507a(6) =614125a(7) =5000211a(8) =39651821a(9) =318611987a(10) =2543302125a(11) =20368783891a(12) =162860787181