Number of subsets of {1..n} such that it is possible to choose a different prime factor of each element.
A370582
Number of subsets of {1..n} such that it is possible to choose a different prime factor of each element.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =6a(5) =12a(6) =20a(7) =40a(8) =52a(9) =72a(10) =116a(11) =232a(12) =320a(13) =640a(14) =1020a(15) =1528a(16) =1792a(17) =3584a(18) =4552a(19) =9104a(20) =12240a(21) =17840a(22) =27896a(23) =55792a(24) =67584a(25) =83968a(26) =130656a(27) =150240a(28) =198528a(29) =397056
External references
- oeis: A370582