a(n) = a(n-1) + a(n-2) + 1 for n>1, a(0)=0, a(1)=7.

Terms

a(0) =0a(1) =7a(2) =8a(3) =16a(4) =25a(5) =42a(6) =68a(7) =111a(8) =180a(9) =292a(10) =473a(11) =766a(12) =1240a(13) =2007a(14) =3248a(15) =5256a(16) =8505a(17) =13762a(18) =22268a(19) =36031a(20) =58300a(21) =94332a(22) =152633a(23) =246966a(24) =399600a(25) =646567a(26) =1046168a(27) =1692736a(28) =2738905a(29) =4431642