a(n) = n^r(n), where r(n) is the digital root of n.

Terms

a(0) =1a(1) =1a(2) =4a(3) =27a(4) =256a(5) =3125a(6) =46656a(7) =823543a(8) =16777216a(9) =387420489a(10) =10a(11) =121a(12) =1728a(13) =28561a(14) =537824a(15) =11390625a(16) =268435456a(17) =6975757441a(18) =198359290368a(19) =19a(20) =400a(21) =9261a(22) =234256a(23) =6436343a(24) =191102976a(25) =6103515625a(26) =208827064576a(28) =28a(29) =841a(30) =27000