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Theorems · Theorem · general topology

continuousWithinAt_diff_singleton

Deprecated since 2026-06-03Use continuousWithinAt_sdiff_singleton instead.

∀ {X : Type u_1} {Y : Type u_2} [inst : TopologicalSpace X] [inst_1 : TopologicalSpace Y] [T1Space X] {x y : X}
  {s : Set X} {f : X → Y}, ContinuousWithinAt f (s \ {y}) x ↔ ContinuousWithinAt f s x

Alias of continuousWithinAt_sdiff_singleton. See also continuousWithinAt_sdiff_self for the case y = x but not requiring T1Space.

Defined in
Mathlib.Topology.Separation.Basic
Cited by
0 results in Mathlib
Foundations
Depth 74 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
TopologicalSpaceTopologicalSpaceT1Space

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