Number of subsets of {1..n} (including empty set) such that the pairwise GCDs of elements are not distinct.
A196720
Number of subsets of {1..n} (including empty set) such that the pairwise GCDs of elements are not distinct.
Terms
- a(0) =1a(1) =2a(2) =4a(3) =8a(4) =13a(5) =25a(6) =33a(7) =61a(8) =81a(9) =116a(10) =140a(11) =256a(12) =282a(13) =530a(14) =606a(15) =692a(16) =823a(17) =1551a(18) =1653a(19) =3173a(20) =3391a(21) =3805a(22) =4177a(23) =8049a(24) =8345a(25) =11524a(26) =12508a(27) =15294a(28) =16204a(29) =31692
External references
- oeis: A196720