PyramidPattern Hollow

function PyramidPattern(n){
let str='';
for(let i=0;i<n;i++){
for(let j=0;j<(n2)-1;j++){
if(i==n-1 ||j==n-1-i ||j==n-1+i){
str+=''
}else{
str+=' '
}

}
str+='\n'

}

return str;
}

console.log(PyramidPattern(10))