Duplicate of A136488.

Terms

a(0) =1a(1) =2a(2) =5a(3) =10a(4) =22a(5) =44a(6) =92a(7) =184a(8) =376a(9) =752a(10) =1520a(11) =3040a(12) =6112a(13) =12224a(14) =24512a(15) =49024a(16) =98176a(17) =196352a(18) =392960a(19) =785920a(20) =1572352a(21) =3144704a(22) =6290432a(23) =12580864a(24) =25163776a(25) =50327552a(26) =100659200a(27) =201318400a(28) =402644992a(29) =805289984