Lightly Documented Features

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(For In[1] see Setup)

In[1]:= ?NumberOfKnots
NumberOfKnots[n] returns the number of knots with n crossings. NumberOfKnots[n, Alternating|NonAlternating] returns the number of knots of the specified type.
In[2]:= NumberOfKnots[16, NonAlternating]
Out[2]= 1008906
In[3]:= ?AlternatingQ
AlternatingQ[K] tries to decide if the knot K is alternating. This function is extremely incomplete; it only works for named knots from the tables, or torus knots.

Among the knots with up to 11 crossings, 564 are alternating and 238 are not:

In[4]:= Total[AlternatingQ /@ AllKnots[{0,11}]]
Out[4]= 238 False + 564 True