a(n) = a(n-1) + a(n-2) + 1, with a(0) = 1 and a(1) = 8.

Terms

a(0) =1a(1) =8a(2) =10a(3) =19a(4) =30a(5) =50a(6) =81a(7) =132a(8) =214a(9) =347a(10) =562a(11) =910a(12) =1473a(13) =2384a(14) =3858a(15) =6243a(16) =10102a(17) =16346a(18) =26449a(19) =42796a(20) =69246a(21) =112043a(22) =181290a(23) =293334a(24) =474625a(25) =767960a(26) =1242586a(27) =2010547a(28) =3253134a(29) =5263682