Largest proper substring of 2^n that is a power of 2 (0 if none).

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =2a(6) =4a(7) =8a(8) =2a(9) =2a(10) =4a(11) =8a(12) =4a(13) =8a(14) =16a(15) =32a(16) =0a(17) =2a(18) =4a(19) =8a(20) =8a(21) =2a(22) =4a(23) =8a(24) =16a(25) =32a(26) =64a(27) =8a(28) =8a(29) =8