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gap-packages / walrus

Computational Methods for Finitely Generated Monoids and Groups
https://gap-packages.github.io/walrus
BSD 3-Clause "New" or "Revised" License
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non-freely cancelled relator in random pregroup presentation #5

Closed colva closed 5 years ago

colva commented 7 years ago 

<pregroup of free group of rank 4>
gap> pr:= RandomPregroupPresentation(pg, 5, 5);
<pregroup presentation with 8 generators and 5 relators>
gap> RSymTest(pr, 1/6);
[ fail, [ [ 2, 0, 0, 0 ], [ 4, 1, 1, 0.0666667 ], [ 5, 1, 1, 0.0666667 ], 
      [ 6, 2, 2, 0.05 ], [ 7, 2, 2, 0.05 ], [ 8, 3, 3, 0.116667 ], 
      [ 9, 3, 3, 0.116667 ], [ 10, 3, 3, 0.116667 ], [ 11, 4, 3, 0.216667 ], 
      [ 12, 4, 3, 0.216667 ], [ 13, 4, 3, 0.216667 ], [ 1, 5, 4, 0.333333 ] ],
  [ 9, 3, 3, 0.116667 ] ]
gap> Places(pr)[2];
(<pregroup relator [ "X4", "X1", "X2", "x2", "X3" ]>(1,X3,X4),X3,"green")```