Triangle read by rows: T(n,k) is the number of permutations p of [n] for which k is the smallest among the positive differences p(i+1) - p(i); k=0 for the reversal of the identity permutation (0<=k<=n-1).
A180190
Triangle read by rows: T(n,k) is the number of permutations p of [n] for which k is the smallest among the positive differences p(i+1) - p(i); k=0 for the reversal of the identity permutation (0<=k<=n-1).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =2a(6) =1a(7) =13a(8) =6a(9) =4a(10) =1a(11) =67a(12) =30a(13) =14a(14) =8a(15) =1a(16) =411a(17) =178a(18) =80a(19) =34a(20) =16a(21) =1a(22) =2921a(23) =1236a(24) =530a(25) =234a(26) =86a(27) =32a(28) =1a(29) =23633
External references
- oeis: A180190