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): |
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<!--$$?K = ConnectedSum[Knot[4,1], Knot[4,1]$$--> |
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Revision as of 20:49, 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 [math]\displaystyle{ K=4_1\#4_1 }[/math] of the knot 4_1 with itself has 8 crossings (unsurprisingly):
It is also nice to know that, as expected, the Jones polynomial of [math]\displaystyle{ K }[/math] is the square of the Jones polynomial of 4_1:
It is less nice to know that the Jones polynomial cannot tell [math]\displaystyle{ K }[/math] apart from the knot 8_9:
But [math]\displaystyle{ K=4_1\#4_1 }[/math] isn't equivalent to 8_9; indeed, their Alexander polynomials are different: