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

Terms

a(0) =0a(1) =6a(2) =7a(3) =14a(4) =22a(5) =37a(6) =60a(7) =98a(8) =159a(9) =258a(10) =418a(11) =677a(12) =1096a(13) =1774a(14) =2871a(15) =4646a(16) =7518a(17) =12165a(18) =19684a(19) =31850a(20) =51535a(21) =83386a(22) =134922a(23) =218309a(24) =353232a(25) =571542a(26) =924775a(27) =1496318a(28) =2421094a(29) =3917413