"DIK" (bracelet, indistinct, unlabeled) transform of 2,2,2,2...

Terms

a(0) =2a(1) =5a(2) =10a(3) =21a(4) =42a(5) =95a(6) =210a(7) =510a(8) =1258a(9) =3249a(10) =8538a(11) =23033a(12) =62778a(13) =173451a(14) =482690a(15) =1353075a(16) =3811362a(17) =10785233a(18) =30625194a(19) =87239997a(20) =249174234a(21) =713416599a(22) =2046945138a(23) =5884580072a(24) =16946835090a(25) =48883925865a(26) =141217957618a(27) =408519816609