Number of permutations of 1..n in which every pair of adjacent numbers as well as the first and the last entries are relatively prime.

A102381

Number of permutations of 1..n in which every pair of adjacent numbers as well as the first and the last entries are relatively prime.

Terms

    a(0) =1a(1) =2a(2) =6a(3) =8a(4) =60a(5) =24a(6) =504a(7) =576a(8) =6480a(9) =5760a(10) =242352a(11) =93312a(12) =6200064a(13) =5612544a(14) =95294880a(15) =136249344a(16) =13687492608a(17) =5022425088a(18) =693149184000a(19) =472559616000

External references