๐-sets in ๐น^{โ}-spaces
๐-sets in ๐น^{โ}-spaces
A <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper P"> <mml:semantics> <mml:mi>P</mml:mi> <mml:annotation encoding="application/x-tex">P</mml:annotation> </mml:semantics> </mml:math> </inline-formula>-set is one which is interior to any zero set which contains it. An <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper F prime"> <mml:semantics> <mml:msup> <mml:mi>F</mml:mi> <mml:mo>โฒ</mml:mo> </mml:msup> <mml:annotation encoding="application/x-tex">Fโ</mml:annotation> </mml:semantics> </mml:math> </inline-formula>-space may be characterized as one in โฆ