Constructible but not shellable example
 Description

Identify the vertices with the same label.
 Properties

Nonshellability is a consequence of the fact that
this example is contractible but has no boundary.
Constructibility can be easily checked.
In particular, it should be noted that having no boundary
and to be contractible do not imply nonconstructibility.
 Datum

cns.dat
 Some table

vertex decomposable?  no 
extendably shellable?  no 
shellable?  no 
constructible?  yes 
CohenMacaulay?  yes 
partitionable?  yes 
topology  contractible 
fvector  (1,12,37,26) 
hvector  (1,9,16,0) 
made by  Hachimori 
 References
 M.Hachimori,
Combinatorics of constructible complexes, PhD thesis.
Note: The number of the bottom vertex was wrongly written on the figure.
It is now fixed.
(Thanks Brent for this correction. 2016.6.13)
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