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removed deprecated tag 'topology'; attempted to make question more readable (I hope I did not change the intended meaning)
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Ricardo Andrade
Ricardo Andrade
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a A space with countable tightness which is not Frecheta Fréchet space?

I need a space with countable tightness which is not Frecheta Fréchet space. In this space, I am searching for a poinpoint with no deleted neighborhood entierelyconsisting entirely of P-poinntspoints.

(PA P-point is thata point x \in X$x \in X$ such that for every G_\delta$G_\delta$ set O$O$ containing x$x$, x \in int(O)$x \in \operatorname{int}(O)$ or equivalently :M_x = O_x$M_x = O_x$, i.e every fixed prime z-filter that contains x$x$ is a z- ultrafilterultrafilter.)

a space with countable tightness which is not Frechet space?

I need a space with countable tightness which is not Frechet space. In this space, I am searching a poin with no deleted neighborhood entierely of P-poinnts.

(P-point is that point x \in X such that for every G_\delta set O containing x, x \in int(O) or equivalently :M_x = O_x i.e every fixed prime z-filter that contains x is a z- ultrafilter.)

A space with countable tightness which is not a Fréchet space?

I need a space with countable tightness which is not a Fréchet space. In this space, I am searching for a point with no deleted neighborhood consisting entirely of P-points.

(A P-point is a point $x \in X$ such that for every $G_\delta$ set $O$ containing $x$, $x \in \operatorname{int}(O)$ or equivalently $M_x = O_x$, i.e every fixed prime z-filter that contains $x$ is a z-ultrafilter.)

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Vahideh Bagheri
Vahideh Bagheri
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a space with countable tightness which is not Frechet space?

I need a space with countable tightness which is not Frechet space. In this space, I am searching a poin with no deleted neighborhood entierely of P-poinnts.

(P-point is that point x \in X such that for every G_\delta set O containing x, x \in int(O) or equivalently :M_x = O_x i.e every fixed prime z-filter that contains x is a z- ultrafilter.)