Number of subsets of {1..n} such that every pair of distinct elements has a different quotient.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =14a(5) =28a(6) =52a(7) =104a(8) =188a(9) =308a(10) =548a(11) =1096a(12) =1784a(13) =3568a(14) =6168a(15) =10404a(16) =16200a(17) =32400a(18) =49968a(19) =99936a(20) =155584a(21) =256944a(22) =433736a(23) =867472a(24) =1297504a(25) =2026288a(26) =3387216a(27) =5692056a(28) =8682912a(29) =17365824