#include<iostream>
#include<string>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<math.h>
#include<complex>
#include<queue>
#include<deque>
#include<stack>
#include<map>
#include<set>
#include<bitset>
#include<functional>
#include<assert.h>
#include<numeric>
using namespace std;
#define REP(i,m,n) for(int i=(int)(m) ; i < (int) (n) ; ++i )
#define rep(i,n) REP(i,0,n)
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
using ll = long long;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;
const ll mod=1e9+7 ;
using namespace std;
struct Fast { Fast(){ std::cin.tie(0); ios::sync_with_stdio(false); } } fast;

template<typename ...Ts>
void show(Ts... ts){
  cout<<"#:";
  auto print=[](auto v){cout<<v<<" ";};
  initializer_list<int>{(void(print(ts)),0)...};
  cout<<endl;
}


int main(void){
    int h,w;
    string s;
    cin>>h>>w;
    vector<vector<int>> m(h+2,vector<int>(w+2,0));
    rep(i,h){
        cin>>s;
        rep(j,w){
            if(s[j]=='#'){
                m[i+1][j+1]=1;
            }else{
                m[i+1][j+1]=0;
            }
        }
    }
    bool flg=true;
    REP(i,1,h){
        REP(j,1,w){
            if(m[i][j]==1){
                if(m[i-1][j-1]+m[i+1][j-1]+m[i-1][j+1]+m[i+1][j+1]==0)flg=false;
            }
        }
    }
    string ans="Yes";
    if(flg)ans="No";
    cout<<ans;
}

