From a problem concerning circulant matrices and Gauss sums.

Terms

a(0) =1a(1) =1a(2) =1a(3) =16a(4) =0a(5) =1a(6) =1a(7) =256a(8) =81a(9) =0a(10) =4641a(11) =16a(12) =1a(13) =1a(14) =0a(15) =4096a(16) =1a(17) =81a(18) =721a(19) =0a(20) =1a(21) =4641a(22) =1a(23) =256a(24) =78125a(25) =1a(26) =6561a(27) =16