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###                                                                              ###
###                                                                              ###
###  LIBRARY OF TRIANGULATIONS                                                   ###
###  by Bruno Benedetti and Frank H. Lutz                                        ###
###  http://page.math.tu-berlin.de/~lutz/stellar/library_of_triangulations.html  ###
###                                                                              ###
###                                                                              ###
###  name of example:                                                            ###
###                                                                              ###
###    BH_4                                                                      ###
###                                                                              ###
###                                                                              ###
###  description:                                                                ###
###                                                                              ###
###    triangulation of Bing's House with four rooms                             ###
###                                                                              ###
###                                                                              ###
###  properties:                                                                 ###
###                                                                              ###
###    f=(57,200,144),                                                           ###
###    H_*=(Z,0,0),                                                              ###
###    contractible, but not collapsible,                                        ###
###    optimal discrete Morse vector: (1,1,1), not perfect                       ###
###                                                                              ###
###                                                                              ###
###  references:                                                                 ###
###                                                                              ###
###    B. Benedetti, C. Lai, D. Lofano, F. H. Lutz.                              ###
###    Random simple-homotopy theory.                                            ###
###    Arxiv:2107.09862 (2021).                                                  ###
###                                                                              ###
###    M. Tancer.                                                                ###
###    Recognition of collapsible complexes is NP-complete.                      ###
###    Discrete Comput. Geom. 55, 21-38 (2016).                                  ###
###                                                                              ###
###    R. H. Bing.                                                               ###
###    Some aspects of the topology of 3-manifolds related                       ###
###    to the Poincaré conjecture.                                               ###
###    Lectures on Modern Mathematics, Vol. II, Wiley, NY, 1964.                 ###
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