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Trait Suggestion: The butterfly space (S143) is not simply connected (P200) #931

Closed david20000813 closed 1 week ago

david20000813 commented 1 week ago

Trait Suggestion

The butterfly space (S143) is not simply connected (P200), but this fact is not known to pi-Base today:

https://topology.pi-base.org/spaces/S000143/properties/P000200

Proof/References

Shown in MartianInvader’s answer to Math StackExchange 4998216.

GeoffreySangston commented 1 week ago

I think we added it a few days ago. Probably pi-base needs to be reset on your end by clicking the reset button there.

(Your link loads the page for me, and it links to MSE + asserts S143 is not simply connected.)

david20000813 commented 1 week ago

I think we added it a few days ago. Probably pi-base needs to be reset on your end by clicking the reset button there.

(Your link loads the page for me, and it links to MSE + asserts S143 is not simply connected.)

@GeoffreySangston Oh yeah you’re right, it is already there. I thought I had synchronized before submitting this issue, but apparently not. Thanks! I’ll close this issue then.