Record indices of A135727(n)/n = max{ A001281^k(n);k=0,1,2,3... }/n (3x-1 problem).

Terms

a(0) =1a(1) =3a(2) =5a(3) =9a(4) =17a(5) =65a(6) =129a(7) =153a(8) =321a(9) =1889a(10) =4097a(11) =10497a(12) =11025a(13) =28161a(14) =149345a(15) =558341a(16) =1467393a(17) =75567105a(18) =299480577a(19) =344371457a(20) =677585217a(21) =788620517a(22) =1951587609a(23) =2672464025a(24) =15958182629a(25) =52002133905a(26) =187559691777a(27) =213121397657