A378382 Number of maximal chains in the poset of all binary words of length <= n, ordered by B covers A iff A_i <= B_{i+k} for all i in A and some k >= 0.

1, 1, 2, 5, 16, 57, 226, 961, 4376, 21041, 106534, 563961, 3112924, 17839993, 105907946, 649432673, 4105783696, 26706965985, 178466243662, 1223248786921, 8589272300516, 61708802126441, 453143009601682, 3397715981566545, 25990997059282456, 202666687407866257

Offset: 0

Author

John Tyler Rascoe, Nov 26 2024

Keywords

• nonn

Examples

			a(3) = 5:
 () < (0) < (0,0) < (0,0,0),
 () < (0) < (0,0) < (0,1),
 () < (0) < (0,0) < (1,0),
 () < (0) < (1) < (0,1),
 () < (0) < (1) < (1,0).
		

Crossrefs

Cf. A034841, A143672, A282698, A317145, column k=2 of A378588, A378608.

Programs

Python

def mchains(n, k): return # See A378588
def A378382_list(max_n): return mchains(max_n,2)