Harary, Frank; Robinson, Robert W. The number of achiral trees. (English) Zbl 0311.05102 J. Reine Angew. Math. 278/279, 322-335 (1975). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 7 Documents MSC: 05C05 Trees 05C10 Planar graphs; geometric and topological aspects of graph theory PDFBibTeX XMLCite \textit{F. Harary} and \textit{R. W. Robinson}, J. Reine Angew. Math. 278/279, 322--335 (1975; Zbl 0311.05102) Full Text: Crelle EuDML Online Encyclopedia of Integer Sequences: Number of unlabeled rooted trees with n nodes (or connected functions with a fixed point). Catalan numbers: C(n) = binomial(2n,n)/(n+1) = (2n)!/(n!(n+1)!). Number of n-node rooted trees of height 4. a(n) = binomial(n, floor(n/2)). Number of partially achiral planted trees with n nodes. Number of compositions of n such that no two adjacent parts are equal (Carlitz compositions).