a(n) is the smallest k such that the 2-adic valuation of A000041(k) equals n.

Terms

a(0) =0a(1) =2a(2) =26a(3) =11a(4) =15a(5) =70a(6) =66a(7) =109a(8) =154a(9) =478a(10) =441a(11) =96a(12) =3693a(13) =15005a(14) =66934a(15) =99420a(16) =18978a(17) =43002a(18) =55943a(19) =972190a(20) =1151214a(21) =2799146a(22) =26801784a(23) =46632889a(24) =15519397a(25) =122101417a(26) =210553237a(27) =289585489a(28) =473093534