Number of sets S = {a_1, a_2, ..., a_k}, with 1 < a_i < a_j <= n such that no a_j divides the product of all the others.
A023995
Number of sets S = {a_1, a_2, ..., a_k}, with 1 < a_i < a_j <= n such that no a_j divides the product of all the others.
Terms
- a(0) =1a(1) =2a(2) =4a(3) =6a(4) =12a(5) =16a(6) =32a(7) =44a(8) =64a(9) =86a(10) =172a(11) =204a(12) =408a(13) =544a(14) =660a(15) =860a(16) =1720a(17) =2080a(18) =4160a(19) =4800a(20) =5792a(21) =7784a(22) =15568a(23) =17440a(24) =23648a(25) =31616a(26) =40976a(27) =46584a(28) =93168a(29) =102768
External references
- oeis: A023995