Number of increasing sequences of addition chain type with maximal element n.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =6a(6) =10a(7) =21a(8) =38a(9) =77a(10) =144a(11) =293a(12) =563a(13) =1131a(14) =2205a(15) =4434a(16) =8711a(17) =17466a(18) =34506a(19) =69169a(20) =137247a(21) =274677a(22) =546081a(23) =1093217a(24) =2177556a(25) =4356756a(26) =8688370a(27) =17381926a(28) =34691608a(29) =69394626