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In this paper, we improve a necessary condition which we gave in
[Topology Appl. 154 (2007) 1502–1515], for 1–bridge braids
in lens spaces to admit an integral surgery yielding the 3–sphere.
As an application, we prove that if the lens space of type (p,q) is
obtained by Berge's surgery on a nontrivial nontorus doubly primitive
knot in the 3–sphere, then ∣q∣≥ 5. To this end,
we completely list up all such lens spaces with ∣q∣<5 and
prove that they are obtained only by torus knots.
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