Triangle read by rows: T(n,k) is the number of permutations of k elements from [1..n] with longest consecutive chain size less than 3.
A340106
Triangle read by rows: T(n,k) is the number of permutations of k elements from [1..n] with longest consecutive chain size less than 3.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =1a(7) =3a(8) =6a(9) =4a(10) =1a(11) =4a(12) =12a(13) =20a(14) =18a(15) =1a(16) =5a(17) =20a(18) =54a(19) =100a(20) =92a(21) =1a(22) =6a(23) =30a(24) =112a(25) =318a(26) =600a(27) =570a(28) =1a(29) =7
External references
- oeis: A340106