a(n) = 3*a(n-1) + 5*a(n-2), with a(0)=2, a(1)=3.

Terms

a(0) =2a(1) =3a(2) =19a(3) =72a(4) =311a(5) =1293a(6) =5434a(7) =22767a(8) =95471a(9) =400248a(10) =1678099a(11) =7035537a(12) =29497106a(13) =123669003a(14) =518492539a(15) =2173822632a(16) =9113930591a(17) =38210904933a(18) =160202367754a(19) =671661627927