a(n+3) = a(n+2) + 3a(n+1) - 2a(n); a(0) = 1, a(1) = -1, a(2)= 3.

Terms

a(0) =1a(1) =-1a(2) =3a(3) =-2a(4) =9a(5) =-3a(6) =28a(7) =1a(8) =91a(9) =38a(10) =309a(11) =241a(12) =1092a(13) =1197a(14) =3991a(15) =5398a(16) =14977a(17) =23189a(18) =57324a(19) =96937a(20) =222531a(21) =398694a(22) =872413a(23) =1623433a(24) =3443284a(25) =6568757a(26) =13651743a(27) =26471446a(28) =54289161a(29) =106400013