Log Canonical Thresholds of Del Pezzo Surfaces
نویسنده
چکیده
, or there are 22 possibilities for (a0, a1, a2, a3) found in [28]. It follows from [12], [28], [4], [1] that the inequality lct(X) > 2/3 holds in the case when X is singular and general. Example 1.4. Let X be a quasismooth hypersurface in P(a0, . . . , a4) of degree ∑4 i=0 ai − 1, where a0 6 a1 6 a2 6 a3 6 a4. Then lct(X) > 3/4 for 1936 values of (a0, a1, a2, a3, a4) (see [29]). Example 1.5. Let X be a smooth hypersurface in P of degree n+ 1 > 3. Then lctm (
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تاریخ انتشار 2007