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Let $G$ be a finite subgroup of $\textrm{Gl}_{n+1}(k)$ (where $k$ is an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth, and still not isomorphic to $\mathbb{P}^n$?

I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Upd. I am deeply grateful to Francesco Polizzi for his answer (including examples). So I would like to ask the following: can one describe weighted projective spaces (or more general $P$ as above) that are locally (set-theoretic) complete interestions or such that the corresponding exceptional locus is of dimension $0$? Is it possible to calculate the number of "extra local equations" for weighted projective spaces? Any extra references would also be very welcome!

Let $G$ be a finite subgroup of $\textrm{Gl}_{n+1}(k)$ (where $k$ is an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth, and still not isomorphic to $\mathbb{P}^n$?

I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Upd. I am deeply grateful to Francesco Polizzi for his answer (including examples). So I would like to ask the following: can one describe weighted projective spaces (or more general $P$ as above) that are locally (set-theoretic) complete interestions? Is it possible to calculate the number of "extra local equations" for weighted projective spaces? Any references (and electronic versions of these text) would also be very welcome!

Let $G$ be a finite subgroup of $Gl_{n+1}(k)$ (for $k$ being an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth (and still not isomorphic to $\mathbb{P}^n$!)?

I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Upd. I am deeply grateful to Francesco Polizzi for his answer (including examples). So I would like to ask the following: can one describe weighted projective spaces (or more general $P$ as above) that are locally (set-theoretic) complete interestions or such that the corresponding exceptional locus is of dimension $0$? Is it possible to calculate the number of "extra local equations" for weighted projective spaces? Any extra references would also be very welcome!

Let $G$ be a finite subgroup of $\textrm{Gl}_{n+1}(k)$ (where $k$ is an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth, and still not isomorphic to $\mathbb{P}^n$?

I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Upd. I am deeply grateful to Francesco Polizzi for his answer (including examples). So I would like to ask the following: can one describe weighted projective spaces (or more general $P$ as above) that are locally (set-theoretic) complete interestions or such that the corresponding exceptional locus is of dimension $0$? Is it possible to calculate the number of "extra local equations" for weighted projective spaces? Any extra references would also be very welcome!

Let $G$ be a finite subgroup of $Gl_{n+1}(k)$ (for $k$ being an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth (and still not isomorphic to $\mathbb{P}^n$!)?

P.S. I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Let $G$ be a finite subgroup of $Gl_{n+1}(k)$ (for $k$ being an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ by $G$ is not isomorphic to $\mathbb{P}^n$ but yet is locally a set-theoretic complete intersection (if we embed it into $\mathbb{P}^m$ for some $m>n$)? It seems that the most "popular" quotients of this type are the so-called weighted projective spaces; so what is known for them? Can $P$ be smooth (and still not isomorphic to $\mathbb{P}^n$!)?

I am also interested in cases when $P$ can locally be "described by not so many extra equations" (say, by $m-3/4 n$ for $P\subset \mathbb{P}^m$) and when the "non-LSTCI locus" (i.e., the set of points where $m-n$ equations are not sufficient) is of dimension less than $n/4$.

Upd. I am deeply grateful to Francesco Polizzi for his answer (including examples). So I would like to ask the following: can one describe weighted projective spaces (or more general $P$ as above) that are locally (set-theoretic) complete interestions or such that the corresponding exceptional locus is of dimension $0$? Is it possible to calculate the number of "extra local equations" for weighted projective spaces? Any extra references would also be very welcome!