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 xAlias 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
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- Setstatement · cited by 53,352
- TopologicalSpacestatement · cited by 24,529
- ContinuousWithinAtstatement · cited by 512
- T1Spacestatement · cited by 275
- continuousWithinAt_sdiff_singletonproof · cited by 1
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