Number of permutations of 3..n+2 with no element divisible by an adjacent element.
A178846
Number of permutations of 3..n+2 with no element divisible by an adjacent element.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =12a(4) =72a(5) =336a(6) =1824a(7) =13152a(8) =134880a(9) =649296a(10) =8572800a(11) =102194400a(12) =1033046880a(13) =12143232960a(14) =210042192960
External references
- oeis: A178846