= Alternating diagram signature formula
{title2=$\sigma(K)=s_A(D)-c_+(D)-1$}
For a reduced connected <alternating knot diagram>, its <knot signature> is $s_A(D)-c_+(D)-1$, where $s_A$ counts circles in the all-$A$ <bracket smoothing state> and $c_+$ counts positive crossings. The convention is that the $A$-smoothing at a positive braid crossing is the <oriented smoothing>, and a positive <trefoil knot> has <knot signature> $-2$. Reversing the global <knot signature> convention negates the formula.
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