Automorphisms of subword-posets

In this paper the automorphism group of two posets, Dk,n and Bm,n is determined. Dk,n is the poset of DNA strands of length at most n, built up with k complement pairs of letters, and partially ordered by the subsequence relation. Bm,n is the set of all subsequences of the word um,n=a1…an defined over the alphabet {0,1,…,(m-1)}, where ai≡i-1(modm). The automorphism group of Bm,n was known already (see G. Burosch, H.-D.O.F. Gronau, J.-M. Laborde, The automorphism group of the subsequence poset Bm,n, Order 16 (2) (1999) 179-194 (2000)), here a short proof is presented as an illustration of the method used in the first part.