a(n) = 20*a(n-2) - 64*a(n-4).

Terms

a(0) =1a(1) =59a(2) =2416a(3) =6230a(4) =47680a(5) =120824a(6) =798976a(7) =2017760a(8) =12928000a(9) =32622464a(10) =207425536a(11) =523312640a(12) =3321118720a(13) =8378415104a(14) =53147140096a(15) =134076293120a(16) =850391203840