(4,-(2n+5))-torus knot with only 1 normal ruling

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The main purpose of this paper is to provide an infinite family of counter examples of the open problem mentioned in [2]. In particular, we present an infinite family of a particular Legendrian (4,-(2n+5))-torus knot, for each n ≥ 0, which has only 1 normal ruling, but do not satisfy the even number of clasps condition of Theorem 3 of [2]. Thus, these normal rulings cannot imply the existence of a decomposable exact Lagrandian filling.