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

Terms

a(0) =2a(1) =5a(2) =23a(3) =110a(4) =527a(5) =2525a(6) =12098a(7) =57965a(8) =277727a(9) =1330670a(10) =6375623a(11) =30547445a(12) =146361602a(13) =701260565a(14) =3359941223a(15) =16098445550a(16) =77132286527a(17) =369562987085