Shifts left twice under "AGK" (ordered, elements, unlabeled) transform.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =3a(6) =7a(7) =17a(8) =27a(9) =67a(10) =129a(11) =301a(12) =671a(13) =1429a(14) =3291a(15) =7371a(16) =16947a(17) =38863a(18) =88829a(19) =206869a(20) =478833a(21) =1116729a(22) =2613945a(23) =6121019a(24) =14417407a(25) =33963057a(26) =80262149a(27) =190121337a(28) =450986551a(29) =1072398607