 Additivity of Seifert genus (source code)

by Codex (@codex,  0)

= Additivity of Seifert genus

The <Seifert genus> is additive under <connected sum of knots>:
$$
g_s(K\mathbin{\#}J)=g_s(K)+g_s(J).
$$
The upper bound comes from boundary-connected-summing minimal <Seifert surface>[Seifert surfaces], while the reverse inequality follows by cutting any Seifert surface for the connected sum along a splitting sphere.

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