A378382 - OEIS

A378382

Number of maximal chains in the poset of compositions with weight <= n and parts of size <= 2, ordered by A covers B iff A_i >= B_{i+k} for all i in B 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

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..25.

EXAMPLE

a(3) = 5:

() < (1) < (1,1) < (1,1,1),

() < (1) < (1,1) < (1,2),

() < (1) < (1,1) < (2,1),

() < (1) < (2) < (1,2),

() < (1) < (2) < (2,1).