Mary has just graduated from one well-known University and is now attending celebration party. Students like to dream of a beautiful life, so they used champagne glasses to construct a small pyramid. The height of the pyramid is n. The top level consists of only 1 glass, that stands on 2 glasses on the second level (counting from the top), then 3 glasses on the third level and so on.The bottom level consists of n glasses.

Vlad has seen in the movies many times how the champagne beautifully flows from top levels to bottom ones, filling all the glasses simultaneously. So he took a bottle and started to pour it in the glass located at the top of the pyramid.

Each second, Vlad pours to the top glass the amount of champagne equal to the size of exactly one glass. If the glass is already full, but there is some champagne flowing in it, then it pours over the edge of the glass and is equally distributed over two glasses standing under. If the overflowed glass is at the bottom level, then the champagne pours on the table. For the purpose of this problem we consider that champagne is distributed among pyramid glasses immediately. Vlad is interested in the number of completely full glasses if he stops pouring champagne in t seconds.

Pictures below illustrate the pyramid consisting of three levels.

<image> <image>

Input

The only line of the input contains two integers n and t (1 ≤ n ≤ 10, 0 ≤ t ≤ 10 000) — the height of the pyramid and the number of seconds Vlad will be pouring champagne from the bottle.

Output

Print the single integer — the number of completely full glasses after t seconds.

Examples

Input

3 5


Output

4


Input

4 8


Output

6

Note

In the first sample, the glasses full after 5 seconds are: the top glass, both glasses on the second level and the middle glass at the bottom level. Left and right glasses of the bottom level will be half-empty.
import com.sun.org.apache.xml.internal.utils.StringComparable;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.*;

public class Main {
    public static void main(String[] args) {
//     Test.testing();
        ConsoleIO io = new ConsoleIO();
        new Main(io).solve();
        io.flush();
    }

    ConsoleIO io;

    Main(ConsoleIO io) {
        this.io = io;
    }

    ArrayList<ArrayList<Integer>> gr;
    boolean[] visit;

    class Pair {
        public Pair(long a, long b) {
            this.a = a;
            this.b = b;
        }

        public long a;
        public long b;
    }

    class Edge {
        public Edge(int u, double v, int c) {
            this.u = u;
            this.v = v;
            this.c = c;
        }

        public int u;
        public double v;
        public int c;
    }

    long MOD = 1_000_000_007;
    int N, M, K;
    int[][] map;
    int move, change, time;

    List<Integer> nums = new ArrayList<>();

    int ff = 1024*16;

    public void solve() {
        int[] nums = io.readIntArray();
        N = nums[0];
        int t = nums[1];
        map = new int[N][N];

        int res = 0;
        map[0][0] = ff * t;
        for (int d = 0; d < N; d++) {
            for (int i = 0; i <= d; i++) {
                int j = d - i;
                int c = map[i][j];
                if (c > ff) {
                    int r = c - ff;
                    map[i][j] = ff;
                    if (i < N - 1)
                        map[i + 1][j] += r / 2;
                    if (j < N - 1)
                        map[i][j + 1] += r / 2;
                }
            }
        }
        for (int i = 0; i < N; i++)
            for (int j = 0; j < N; j++) if(i+j<N)
                if (map[i][j] >= ff) res++;

        io.writeLine(res + "");
    }

    long gcd(long a, long b) {
        if (a < b) return gcd(b, a);
        if (b == 0) return a;
        return gcd(b, a % b);
    }
}

class ConsoleIO {
    BufferedReader br;
    PrintWriter out;
    public ConsoleIO(){br = new BufferedReader(new InputStreamReader(System.in));out = new PrintWriter(System.out);}
    public void flush(){this.out.close();}
    public void writeLine(String s) {this.out.println(s);}
    public void writeInt(int a) {this.out.print(a);this.out.print(' ');}
    public void writeWord(String s){
        this.out.print(s);
    }
    public int read(char[] buf, int len){try {return br.read(buf,0,len);}catch (Exception ex){ return -1; }}
    public String readLine() {try {return br.readLine();}catch (Exception ex){ return "";}}
    public long readLong() {
        return Long.parseLong(this.readLine());
    }
    public int readInt() {
        return Integer.parseInt(this.readLine().trim());
    }
    public long[] readLongArray() {
        String[]n=this.readLine().trim().split("\\s+");long[]r=new long[n.length];
        for(int i=0;i<n.length;i++)r[i]=Long.parseLong(n[i]);
        return r;
    }
    public int[] readIntArray() {
        String[]n=this.readLine().trim().split("\\s+");int[]r=new int[n.length];
        for(int i=0;i<n.length;i++)r[i]=Integer.parseInt(n[i]);
        return r;
    }
    public int[] readIntArray(int n) {
        int[] res = new int[n];
        char[] all = this.readLine().toCharArray();
        int cur = 0;boolean have = false;
        int k = 0;
        boolean neg = false;
        for(int i = 0;i<all.length;i++){
            if(all[i]>='0' && all[i]<='9'){
                cur = cur*10+all[i]-'0';
                have = true;
            }else if(all[i]=='-') {
                neg = true;
            }
            else if(have){
                res[k++] = neg?-cur:cur;
                cur = 0;
                have = false;
                neg = false;
            }
        }
        if(have)res[k++] = neg?-cur:cur;
        return res;
    }
    public void writeIntArray(int[] a) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < a.length; i++) {if (i > 0) sb.append(' ');sb.append(a[i]);}
        this.writeLine(sb.toString());
    }
}



