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.
//package com.codeforces.competitions.year2016.apriltojune.round354div2;

import java.io.*;
import java.util.*;

public final class TaskB
{
    public static void main(String[] args)
    {
        InputReader in = new InputReader(System.in);
        OutputWriter out = new OutputWriter(System.out);

		Solver solver = new Solver(in, out);
		solver.solve(1);

        out.flush();

        in.close();
        out.close();
    }

    static class Solver
    {
        int n, t, full;
		Node[][] nodes;
        InputReader in;
        OutputWriter out;

        public Solver(InputReader in, OutputWriter out)
        {
        	this.in = in;
        	this.out = out;
        }

		void solve(int testNumber)
		{
			n = in.nextInt();
			t = in.nextInt();

			nodes = new Node[n][];

			nodes[0] = new Node[1];

			insert(0, 0, 1, t);

			for (int i = 0; i < n; i++)
			{
//				System.out.println("***** i : " + i);
				for (int j = 0; j < i + 1; j++)
				{
					if (nodes[i] == null || nodes[i][j] == null)
						continue;

//					System.out.println("j : " + j + ", vol : " + nodes[i][j].volume);
					if (nodes[i][j].volume >= 1d)
						full++;
				}
			}

			out.println(full);
		}

		void insert(int level, int index, double inFlow, double time)
		{
/*			System.out.println("&&&& level : " + level + ", index : " + index + ", inFlow : " + inFlow + ", time : "
					+ time);*/

			if (level == n)
				return;

			if (nodes[level] == null)
				nodes[level] = new Node[level + 1];

			if (time <= 0)
				return;

			if (nodes[level][index] == null)
				nodes[level][index] = new Node(index, inFlow);

			if (inFlow == 0d)
				return;

			double secondsTaken = 0d;

			if (nodes[level][index].volume < 1d)
				secondsTaken = (1d - nodes[level][index].volume) / inFlow;

			nodes[level][index].volume += time * inFlow;

			if (nodes[level][index].volume >= 1d)
			{
				insert(level + 1, index, inFlow / 2d, time - secondsTaken);
				insert(level + 1, index + 1, inFlow / 2d, time - secondsTaken);
			}
		}

		class Node
		{
			int index;
			double volume, inFlow;

			public Node(int index, double flow)
			{
				this.index = index;
				this.inFlow = flow;
			}

		}

	}

    static class InputReader
    {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream)
        {
            this.stream = stream;
        }

        public int read()
        {
            if (numChars == -1)
                throw new InputMismatchException();

            if (curChar >= numChars)
            {
                curChar = 0;
                try
                {
                    numChars = stream.read(buf);
                } catch (IOException e)
                {
                    throw new InputMismatchException();
                }
                if (numChars <= 0)
                    return -1;
            }

            return buf[curChar++];
        }

        public int nextInt()
        {
            int c = read();

            while (isSpaceChar(c))
                c = read();

            int sgn = 1;

            if (c == '-')
            {
                sgn = -1;
                c = read();
            }

            int res = 0;

            do
            {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();

                res *= 10;
                res += c & 15;

                c = read();
            } while (!isSpaceChar(c));

            return res * sgn;
        }

        public int[] nextIntArray(int arraySize)
        {
            int array[] = new int[arraySize];

            for (int i = 0; i < arraySize; i++)
                array[i] = nextInt();

            return array;
        }

        public long nextLong()
        {
            int c = read();

            while (isSpaceChar(c))
                c = read();

            int sign = 1;

            if (c == '-')
            {
                sign = -1;

                c = read();
            }

            long result = 0;

            do
            {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();

                result *= 10;
                result += c & 15;

                c = read();
            } while (!isSpaceChar(c));

            return result * sign;
        }

        public long[] nextLongArray(int arraySize)
        {
            long array[] = new long[arraySize];

            for (int i = 0; i < arraySize; i++)
                array[i] = nextLong();

            return array;
        }

        public float nextFloat() // problematic
        {
            float result, div;
            byte c;

            result = 0;
            div = 1;
            c = (byte) read();

            while (c <= ' ')
                c = (byte) read();

            boolean isNegative = (c == '-');

            if (isNegative)
                c = (byte) read();

            do
            {
                result = result * 10 + c - '0';
            } while ((c = (byte) read()) >= '0' && c <= '9');

            if (c == '.')
                while ((c = (byte) read()) >= '0' && c <= '9')
                    result += (c - '0') / (div *= 10);

            if (isNegative)
                return -result;

            return result;
        }

        public double nextDouble() // not completely accurate
        {
            double ret = 0, div = 1;
            byte c = (byte) read();

            while (c <= ' ')
                c = (byte) read();

            boolean neg = (c == '-');

            if (neg)
                c = (byte) read();

            do
            {
                ret = ret * 10 + c - '0';
            } while ((c = (byte) read()) >= '0' && c <= '9');

            if (c == '.')
                while ((c = (byte) read()) >= '0' && c <= '9')
                    ret += (c - '0') / (div *= 10);

            if (neg)
                return -ret;

            return ret;
        }

        public String next()
        {
            int c = read();

            while (isSpaceChar(c))
                c = read();

            StringBuilder res = new StringBuilder();

            do
            {
                res.appendCodePoint(c);

                c = read();
            } while (!isSpaceChar(c));

            return res.toString();
        }

        public boolean isSpaceChar(int c)
        {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public String nextLine()
        {
            int c = read();

            StringBuilder result = new StringBuilder();

            do
            {
                result.appendCodePoint(c);

                c = read();
            } while (!isNewLine(c));

            return result.toString();
        }

        public boolean isNewLine(int c)
        {
            return c == '\n';
        }

        public void close()
        {
            try
            {
                stream.close();
            } catch (IOException e)
            {
                e.printStackTrace();
            }
        }

    }

    static class OutputWriter
    {
        private PrintWriter writer;

        public OutputWriter(OutputStream stream)
        {
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
                    stream)));
        }

        public OutputWriter(Writer writer)
        {
            this.writer = new PrintWriter(writer);
        }

        public void println(int x)
        {
            writer.println(x);
        }

        public void print(int x)
        {
            writer.print(x);
        }

        public void println(int array[], int size)
        {
            for (int i = 0; i < size; i++)
                println(array[i]);
        }

        public void print(int array[], int size)
        {
            for (int i = 0; i < size; i++)
                print(array[i] + " ");
        }

        public void println(long x)
        {
            writer.println(x);
        }

        public void print(long x)
        {
            writer.print(x);
        }

        public void println(long array[], int size)
        {
            for (int i = 0; i < size; i++)
                println(array[i]);
        }

        public void print(long array[], int size)
        {
            for (int i = 0; i < size; i++)
                print(array[i]);
        }

        public void println(float num)
        {
            writer.println(num);
        }

        public void print(float num)
        {
            writer.print(num);
        }

        public void println(double num)
        {
            writer.println(num);
        }

        public void print(double num)
        {
            writer.print(num);
        }

        public void println(String s)
        {
            writer.println(s);
        }

        public void print(String s)
        {
            writer.print(s);
        }

        public void println()
        {
            writer.println();
        }

        public void printSpace()
        {
            writer.print(" ");
        }

        public void flush()
        {
            writer.flush();
        }

        public void close()
        {
            writer.close();
        }

    }

	static class CMath
	{
		static long power(long number, long power)
		{
			if (number == 1 || number == 0 || power == 0)
				return 1;

			if (power == 1)
				return number;

			if (power % 2 == 0)
				return power(number * number, power / 2);
			else
				return power(number * number, power / 2) * number;
		}

		static long modPower(long number, long power, long mod)
		{
			if (number == 1 || number == 0 || power == 0)
				return 1;

			number = mod(number, mod);

			if (power == 1)
				return number;

			long square = mod(number * number, mod);

			if (power % 2 == 0)
				return modPower(square, power / 2, mod);
			else
				return mod(modPower(square, power / 2, mod) * number, mod);
		}

		static long moduloInverse(long number, long mod)
		{
			return modPower(number, mod - 2, mod);
		}

		static long mod(long number, long mod)
		{
			return number - (number / mod) * mod;
		}

	}

}
