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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:                                                            ###
###                                                                              ###
###    regular_2_21_23_1                                                         ###
###                                                                              ###
###                                                                              ###
###  description:                                                                ###
###                                                                              ###
###    regular 21-vertex triangulation                                           ###
###    of the orientable surface of genus 15                                     ###
###                                                                              ###
###                                                                              ###
###  properties:                                                                 ###
###                                                                              ###
###    f=(21,147,98),                                                            ###
###    H_*=(Z,Z^30,Z),                                                           ###
###    perfect discrete Morse vector: (1,30,1)                                   ###
###                                                                              ###
###                                                                              ###
###  references:                                                                 ###
###                                                                              ###
###    F. H. Lutz.                                                               ###
###    Triangulated Manifolds with Few Vertices and                              ###
###    Vertex-Transitive Group Actions. Dissertation.                            ###
###    Shaker Verlag, Aachen, 1999, 146 pages.                                   ###
###                                                                              ###
###    B. Benedetti and F. H. Lutz.                                              ###
###    Random discrete Morse theory and a new library of triangulations.         ###
###    Exp. Math. 23, 66-94 (2014).                                              ###
###                                                                              ###
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facets:=[ [ 1, 8, 16 ], [ 1, 8, 21 ], [ 1, 9, 17 ], [ 1, 9, 19 ], [ 1, 10, 15 ], 
  [ 1, 10, 20 ], [ 1, 11, 16 ], [ 1, 11, 18 ], [ 1, 12, 19 ], [ 1, 12, 21 ], 
  [ 1, 13, 15 ], [ 1, 13, 17 ], [ 1, 14, 18 ], [ 1, 14, 20 ], [ 2, 8, 19 ], 
  [ 2, 8, 21 ], [ 2, 9, 15 ], [ 2, 9, 17 ], [ 2, 10, 18 ], [ 2, 10, 20 ], 
  [ 2, 11, 16 ], [ 2, 11, 21 ], [ 2, 12, 17 ], [ 2, 12, 19 ], [ 2, 13, 15 ], 
  [ 2, 13, 20 ], [ 2, 14, 16 ], [ 2, 14, 18 ], [ 3, 8, 17 ], [ 3, 8, 19 ], 
  [ 3, 9, 15 ], [ 3, 9, 20 ], [ 3, 10, 16 ], [ 3, 10, 18 ], [ 3, 11, 19 ], 
  [ 3, 11, 21 ], [ 3, 12, 15 ], [ 3, 12, 17 ], [ 3, 13, 18 ], [ 3, 13, 20 ], 
  [ 3, 14, 16 ], [ 3, 14, 21 ], [ 4, 8, 15 ], [ 4, 8, 17 ], [ 4, 9, 18 ], 
  [ 4, 9, 20 ], [ 4, 10, 16 ], [ 4, 10, 21 ], [ 4, 11, 17 ], [ 4, 11, 19 ], 
  [ 4, 12, 15 ], [ 4, 12, 20 ], [ 4, 13, 16 ], [ 4, 13, 18 ], [ 4, 14, 19 ], 
  [ 4, 14, 21 ], [ 5, 8, 15 ], [ 5, 8, 20 ], [ 5, 9, 16 ], [ 5, 9, 18 ], 
  [ 5, 10, 19 ], [ 5, 10, 21 ], [ 5, 11, 15 ], [ 5, 11, 17 ], [ 5, 12, 18 ], 
  [ 5, 12, 20 ], [ 5, 13, 16 ], [ 5, 13, 21 ], [ 5, 14, 17 ], [ 5, 14, 19 ], 
  [ 6, 8, 18 ], [ 6, 8, 20 ], [ 6, 9, 16 ], [ 6, 9, 21 ], [ 6, 10, 17 ], 
  [ 6, 10, 19 ], [ 6, 11, 15 ], [ 6, 11, 20 ], [ 6, 12, 16 ], [ 6, 12, 18 ], 
  [ 6, 13, 19 ], [ 6, 13, 21 ], [ 6, 14, 15 ], [ 6, 14, 17 ], [ 7, 8, 16 ], 
  [ 7, 8, 18 ], [ 7, 9, 19 ], [ 7, 9, 21 ], [ 7, 10, 15 ], [ 7, 10, 17 ], 
  [ 7, 11, 18 ], [ 7, 11, 20 ], [ 7, 12, 16 ], [ 7, 12, 21 ], [ 7, 13, 17 ], 
  [ 7, 13, 19 ], [ 7, 14, 15 ], [ 7, 14, 20 ] ];