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Knots with g(E(K)) = 2 and g(E(K#K#K)) = 6 and Morimoto's Conjecture

Tsuyoshi Kobayashi·Yo'av Rieck
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Abstract

We show that there exist knots K in S^3 with g(E(K))=2 and g(E(K#K#K))=6. Together with Theorem~1.5 of [1], this proves existence of counterexamples to Morimoto's Conjecture (Conjecture 1.5 of [2]). This is a special case of arxiv.org/abs/math.GT/0701765 [1] Tsuyoshi Kobayashi and Yo'av Rieck. On the growth rate of the tunnel number of knots. J. Reine Angew. Math., 592:63--78, 2006. [2] Kanji Morimoto. On the super additivity of tunnel number of knots.Math. Ann., 317(3):489--508, 2000.

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Tsuyoshi Kobayashi, Yo'av Rieck. 2007-03-13. Knots with g(E(K)) = 2 and g(E(K#K#K)) = 6 and Morimoto's Conjecture. https://arxiv.org/abs/math/0701766

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