Number of permutations of 2..n+1 with no element divisible by an adjacent element.
A178845
Number of permutations of 2..n+1 with no element divisible by an adjacent element.
Terms
- a(0) =1a(1) =2a(2) =2a(3) =12a(4) =20a(5) =180a(6) =648a(7) =5784a(8) =36936a(9) =485040a(10) =2034876a(11) =33492048a(12) =373375392a(13) =4974252864a(14) =52465459392
External references
- oeis: A178845