Number of permutations of 5..n+4 with no element greater than or equal to the sum of its neighbors.
A180893
Number of permutations of 5..n+4 with no element greater than or equal to the sum of its neighbors.
Terms
- a(0) =1a(1) =0a(2) =2a(3) =6a(4) =30a(5) =180a(6) =1200a(7) =8988a(8) =72984a(9) =652062a(10) =6265640a(11) =65368816a(12) =728437140a(13) =8716755900a(14) =110651859874
External references
- oeis: A180893