Structure and Operations: Difference between revisions

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The connected sum <math>K=4_1\#4_1</math> of the knot [[4_1]] with itself has 8 crossings (unsurprisingly):
The connected sum <math>K=4_1\#4_1</math> of the knot [[4_1]] with itself has 8 crossings (unsurprisingly):


<!--$$?K = ConnectedSum[Knot[4,1], Knot[4,1]$$-->
<!--$$?K = ConnectedSum[Knot[4,1], Knot[4,1]]$$-->
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Revision as of 20:50, 24 August 2005

(For In[1] see Setup)



Thus here's one tautology and one easy example:


And another easy example:



For example,


The connected sum of the knot 4_1 with itself has 8 crossings (unsurprisingly):


It is also nice to know that, as expected, the Jones polynomial of is the square of the Jones polynomial of 4_1:


It is less nice to know that the Jones polynomial cannot tell apart from the knot 8_9:


But isn't equivalent to 8_9; indeed, their Alexander polynomials are different: