a(n) = floor(sqrt(n)^sqrt(n)).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =6a(5) =8a(6) =13a(7) =18a(8) =27a(9) =38a(10) =53a(11) =73a(12) =101a(13) =139a(14) =189a(15) =256a(16) =344a(17) =460a(18) =612a(19) =811a(20) =1070a(21) =1406a(22) =1842a(23) =2403a(24) =3125a(25) =4050a(26) =5233a(27) =6742a(28) =8662a(29) =11098