#include<bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pair<int, int> > vii;
#define rrep(i, m, n) for(int (i)=(m); (i)<(n);  (i)++)
#define erep(i, m, n) for(int (i)=(m); (i)<=(n); (i)++)
#define  rep(i, n)    for(int (i)=0; (i)<(n);  (i)++)
#define  rev(i, n)    for(int (i)=(n)-1; (i)>=0; (i)--)
#define vrep(i, c)    for(__typeof((c).begin())i=(c).begin(); i!=(c).end(); i++)
#define  ALL(v)       (v).begin(), (v).end()
#define mp            make_pair
#define pb            push_back
template<class T1, class T2> inline void minup(T1& m, T2 x){ if(m>x) m=static_cast<T2>(x); }
template<class T1, class T2> inline void maxup(T1& m, T2 x){ if(m<x) m=static_cast<T2>(x); }

#define INF 1000000000
#define MOD 1000000007
#define EPS 1E-12

const int MAX_N = 3000;
int n;
int A[MAX_N];
int dp[2][MAX_N][MAX_N];
int res;

int main()
{
  cin >> n;
  rep(i, n) cin >> A[i];

  rep(d, n) rep(L, n){
    int R = L + d;
    if(R > n-1) break;

    if(L == R) dp[0][L][R] = dp[1][L][R] = 1;

    maxup(dp[0][L][R], dp[0][L][R-1]);
    maxup(dp[1][L][R], dp[1][L+1][R]);

    if(A[L] < A[R]) maxup(dp[0][L][R], dp[1][L+1][R]+1);
    if(A[L] > A[R]) maxup(dp[1][L][R], dp[0][L][R-1]+1);
  }

  rep(i, n) rep(j, n) maxup(res, max(dp[0][i][j], dp[1][i][j]));

  cout << res << endl;

  return 0;
}