import re
n=2
p = r'\b(\w+)(?:\.+\1){{{0},}}\b|(\b(\w+)(?:\.+\3){{{1}}}\b)'.format(n,n-1)
s = 'My.name.name.is.Inigo.Montoya.You.killed.my.father.father.father.Prepare.to.die-'
print([x.group(2) for x in re.finditer(p, s) if x.group(2)])
# ['name.name']