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# links.py
# Search for link complements in the 5-tetrahedron census.
# Note: The pound sign (#) introduces comments.
from SnapPea import *
# Examine each Triangulation in the 5-tetrahedron census.
for t in CuspedCensus():
# For each cusp, do a Dehn filling on the shortest
# curve, which, by SnapPea's convention, is the
# meridional filling (1,0).
for i in range(t.get_num_cusps()):
t.set_cusp(i, 1, 0)
# We now have a closed manifold.
# Look at its fundamental group, and if the
# number of generators is zero (meaning the
# group is trivial), print the name of
# the original Triangulation, which we have shown
# to be a link complement in a homotopy sphere.
if t.fundamental_group().num_generators() == 0:
print t.get_name()
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