a(n) = A284016(n)^2.

Terms

a(0) =1a(1) =4a(2) =4a(3) =16a(4) =100a(5) =784a(6) =7056a(7) =69696a(8) =736164a(9) =8179600a(10) =94556176a(11) =1128422464a(12) =13823175184a(13) =173075968576