Number of permutations of 4..n+3 with no element divisible by an adjacent element.
A178847
Number of permutations of 4..n+3 with no element divisible by an adjacent element.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =24a(4) =72a(5) =480a(6) =2640a(7) =23040a(8) =128640a(9) =1444320a(10) =14549760a(11) =159007680a(12) =1556058240a(13) =24239980800a(14) =301025439360
External references
- oeis: A178847