Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,k+n} having excedance set {1,2,...,k} (the empty set for k=0), 0 <= k <= n-1.
A136126
Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,k+n} having excedance set {1,2,...,k} (the empty set for k=0), 0 <= k <= n-1.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =1a(7) =7a(8) =7a(9) =1a(10) =1a(11) =15a(12) =31a(13) =15a(14) =1a(15) =1a(16) =31a(17) =115a(18) =115a(19) =31a(20) =1a(21) =1a(22) =63a(23) =391a(24) =675a(25) =391a(26) =63a(27) =1a(28) =1a(29) =127
External references
- oeis: A136126