Duplicate of A007059.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =3a(5) =5a(6) =8a(7) =14a(8) =24a(9) =43a(10) =77a(11) =140a(12) =256a(13) =472a(14) =874a(15) =1628a(16) =3045a(17) =5719a(18) =10780a(19) =20388