a(n) = floor( phi*a(n-1) ) + floor( phi*a(n-2) ), where phi is the golden ratio.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =4a(5) =9a(6) =20a(7) =46a(8) =106a(9) =245a(10) =567a(11) =1313a(12) =3041a(13) =7044a(14) =16317a(15) =37798a(16) =87559a(17) =202831a(18) =469860a(19) =1088436a(20) =2521375a(21) =5840796a(22) =13530276a(23) =31343052a(24) =72606569a(25) =168194019a(26) =389623535a(27) =902567761a(28) =2090809436a(29) =4843386045