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

Terms

a(0) =0a(1) =2a(2) =2a(3) =5a(4) =8a(5) =16a(6) =28a(7) =53a(8) =98a(9) =183a(10) =341a(11) =637a(12) =1188a(13) =2218a(14) =4140a(15) =7728a(16) =14426a(17) =26930a(18) =50271a(19) =93844a(20) =175184a(21) =327026a(22) =610479a(23) =1139618a(24) =2127393a(25) =3971333a(26) =7413527a(27) =13839278a(28) =25834616a(29) =48227038