#include <bits/stdc++.h>
                            #include<iostream>
                            #include<cstdio>
                            #include<vector>
                            #include<queue>
                            #include<map>
                            #include<cstring>
                            #include<string>
                            #include <math.h>
                            #include<algorithm>
                        //    #include <boost/multiprecision/cpp_int.hpp>
                            #include<functional>
                     #define int long long
                            #define inf  1000000007
                            #define pa pair<int,int>
                            #define ll long long
                            #define pal pair<double,int>
                            #define ppa pair<string,pa>
                            #define ssa pair<string,int>
                            #define  mp make_pair
                            #define  pb push_back
                            #define EPS (1e-10)
                            #define equals(a,b) (fabs((a)-(b))<EPS)
                     
                            using namespace std;
                     //priority_queue<int, vector<int>, greater<int> > que;
                            class Point{
                            	public:
                            	double x,y;
                            	Point(double x=0,double y=0):x(x),y(y) {}
                            	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                            	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                            	Point operator * (double a) {return Point(x*a,y*a);}
                            	Point operator / (double a) {return Point(x/a,y/a);}
                            	double absv() {return sqrt(norm());}
                            	double norm() {return x*x+y*y;}
                            	bool operator < (const Point &p) const{
                            		return x != p.x ? x<p.x: y<p.y;
                            	}
                            	bool operator == (const Point &p) const{
                            		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                            	}
                            };
                            typedef Point Vector;
                     
                            struct Segment{
                            Point p1,p2;
                            };
                     
                        double hen(Vector a){
                        if(fabs(a.x)<EPS && a.y>0) return acos(0);
                        else if(fabs(a.x)<EPS && a.y<0) return 3*acos(0);
                        else if(fabs(a.y)<EPS && a.x<0) return 2*acos(0);
                        else if(fabs(a.y)<EPS && a.x>0) return 0.0;
                        else if(a.y>0) return acos(a.x/a.absv());
                        else return 2*acos(0)+acos(-a.x/a.absv());
                     
                        }
                     
                string itos( int i ) {
                ostringstream s ;
                s << i ;
                return s.str() ;
                }
                 
                int gcd(int v,int b){
                	if(v>b) return gcd(b,v);
                	if(v==b) return b;
                	if(b%v==0) return v;
                	return gcd(v,b%v);
                }
                            double dot(Vector a,Vector b){
                            	return a.x*b.x+a.y*b.y;
                            }
                            double cross(Vector a,Vector b){
                            	return a.x*b.y-a.y*b.x;
                            }
                        
                double distans(double x1,double y1,double x2,double y2){
                	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                	return sqrt(rr);
                	
                }


                         //----------------kokomade tenpure------------

int a[100002]={0}; 
signed main(){
int n,k;
cin>>n;
	for(int i=0;i<n;i++){
		cin>>k;
		a[k]++;
	} 
	
	int d=0;
	for(int i=0;i<=100000;i++){
		if(a[i]>0){
			d=i;
			break;
		}
	}
	
	if(a[d]+a[d+1]<n){
		cout<<"No"<<endl;
		return 0;
	}
//	cout<<"s"<<endl;
	if(a[d]==n){
		if(1<=d && n/2 >=d) cout<<"Yes"<<endl;
		else if (d==n-1) cout<<"Yes"<<endl;
		else cout<<"No"<<endl;
		return 0;
	}
	
	int a1=a[d],a2=a[d+1];
	int c=d+1;
	
	for(int i=1;i<c;i++){
		// a1 ni i
		//a2 ni c-1;
	//cout<<i<<endl;
		if(a1<i || a2<c-i) continue;
		
		if(a1==i && a2==c-i){
			continue;
		}
		
		if(a1==i){
		//	cout<<"s"<<endl;
		//	cout<<a2<<" "<<c-i<<endl;
			if(a2 <2*(c-i)){
				continue;
			}
			if(c==a1+c-i){
		//		cout<<"s"<<endl;
				cout<<"Yes"<<endl;
				return 0;
			}
			continue;
			
		}
		if(a2==c-i){
			if(a1<2*i) continue;
			if(c==i+a2 ){
			//	cout<<"Yes"<<endl;
			//	return 0;
				continue;
			}
			continue;
		}
		
		if(a1<2*i || a2<2*(c-i)) continue;
		
	}
	cout<<"No"<<endl;
	return 0;
}

Measured memory_bytes: 1024