The purpose of thes paper is to show regularity of (0,1,... r-2,r) and (0,1,... r-2,r)* interpolations on the sets obtained by projecting vertically the zeros of
\((1-x^2)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha , \beta <= \frac {1}{2})\\ (1-x)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha<= \frac {1}{2} ,-1< \beta <= \frac {1}{2})\)
and
\((1+x)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha<=\frac {1}{2} , -1 <\beta <= \frac {1}{2})\\ \)
respectively onto the unit circle, where \(P_n^{ ({\alpha , \beta})}(x)\) stand for the 
th Jacobi polynomial.
Regularity of (0,1,... r-2,r) and (0,1,...,r-2,r) Interpolations on Some Sets of the Unit Circle — https://www.rayeshmand.ir/download/regularity-of-01-r-2r-and-01r-2r-interpolations-on-some-sets-of-the-unit-circle