As suggested earlier: +1284 for vice.
Shame you cut the top of the post off. It might still work. Invert bike/ frame. Tighten top of post in vice. You might wreck the post. Then use all the lovely leverage of the frame/ bike to turn the the post free.
@Itisaboutthebike started
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As suggested earlier: +1284 for vice.
Shame you cut the top of the post off. It might still work. Invert bike/ frame. Tighten top of post in vice. You might wreck the post. Then use all the lovely leverage of the frame/ bike to turn the the post free.