a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = -2, a(1) = -2, a(2) = 2, a(3) = 1.

Terms

a(0) =-2a(1) =-2a(2) =2a(3) =1a(4) =15a(5) =18a(6) =57a(7) =79a(8) =184a(9) =271a(10) =551a(11) =838a(12) =1581a(13) =2451a(14) =4416a(15) =6931a(16) =12115a(17) =19174a(18) =32825a(19) =52255a(20) =88152a(21) =140919a(22) =235215a(23) =377158a(24) =624661a(25) =1003867a(26) =1653104a(27) =2661067a(28) =4363323a(29) =7032582