Partial sums of A000219.

Terms

a(0) =1a(1) =2a(2) =5a(3) =11a(4) =24a(5) =48a(6) =96a(7) =182a(8) =342a(9) =624a(10) =1124a(11) =1983a(12) =3462a(13) =5947a(14) =10114a(15) =16993a(16) =28290a(17) =46624a(18) =76225a(19) =123555a(20) =198833a(21) =317627a(22) =504102a(23) =794885a(24) =1246079a(25) =1942112a(26) =3010857a(27) =4643515a(28) =7126749a(29) =10886361