a(n) is the least odd number 2^n - m minimizing A007947(m*(2^n - m)).

Terms

a(0) =1a(1) =3a(2) =7a(3) =15a(4) =27a(5) =63a(6) =125a(7) =243a(8) =343a(9) =999a(10) =1805a(11) =3721a(12) =8181a(13) =16335a(14) =32761a(15) =65533a(16) =112847a(17) =190269a(18) =519375a(19) =1046875a(20) =1953125a(21) =4192479a(22) =8385125a(23) =16775019a(24) =24398405a(25) =66976875a(26) =134216625