Problem: Everyone knows what the Fibonacci sequence is. This sequence can be defined by the recurrence relation: 

F1 = 1, F2 = 2, Fi = Fi - 1 + Fi - 2 (i > 2).

We'll define a new number sequence Ai(k) by the formula: 

Ai(k) = Fi × ik (i ≥ 1).

In this problem, your task is to calculate the following sum: A1(k) + A2(k) + ... + An(k). The answer can be very large, so print it modulo 1000000007 (109 + 7).

Input

The first line contains two space-separated integers n, k (1 ≤ n ≤ 1017; 1 ≤ k ≤ 40).

Output

Print a single integer — the sum of the first n elements of the sequence Ai(k) modulo 1000000007 (109 + 7).

Examples

Input

1 1


Output

1


Input

4 1


Output

34


Input

5 2


Output

316


Input

7 4


Output

73825

Solution (in JAVA):

Solution:
import java.io.*;
import java.util.*;
import java.lang.*;

public class Main {
    final static boolean debug = false;
    final static String fileName = "";
    final static boolean useFiles = false;

    public static void main(String[] args) throws FileNotFoundException {
        long start;
        if (debug)
            start = System.nanoTime();
        InputStream inputStream;
        OutputStream outputStream;
        if (useFiles) {
            inputStream = new FileInputStream(fileName + ".in");
            outputStream = new FileOutputStream(fileName + ".out");
        } else {
            inputStream = System.in;
            outputStream = System.out;
        }
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Task solver = new Task(in, out);
        solver.solve();
        if(debug)
            out.println((System.nanoTime() - start) / 1e+9);
        out.close();
    }
}
class Task {
    final int mod = (int) (1e9 + 7);

    long[][] mul(long[][] a, long[][] b) {
        long[][] c = new long[a.length][a.length];
        for (int i = 0; i < a.length; ++i) {
            for (int j = 0; j < a.length; ++j) {
                for (int k = 0; k < a.length; ++k) {
                    c[i][j] = (c[i][j] + a[i][k] * b[k][j]) % mod;
                }
            }
        }
        return c;
    }

    long[][] pow(long[][] a, long pow) {
        long[][] r = new long[a.length][a.length];
        for (int i = 0; i < a.length; ++i) {
            r[i][i] = 1;
        }
        while (pow > 0) {
            if (pow % 2 == 1) {
                r = mul(r, a);
            }
            pow >>= 1;
            a = mul(a, a);
        }
        return r;
    }

    public void solve() {
        long n = in.nextLong();
        int k = in.nextInt();
        k++;
        long[][] b = new long[2 * k + 1][2 * k + 1];
        for (int i = 0; i < k; i++) {
            b[i][k] = b[k + i][0] = b[i][0] = 1;
            for (int j = 1; j <= i; j++)
                b[i + k][j] = b[i][j + k] = b[i][j] = (b[i - 1][j - 1] + b[i - 1][j]) % mod;
        }
        for (int i = 0; i < 2 * k; i++)
            b[2 * k][i] = b[k - 1][i];
        b[2 * k][2 * k] = 1;

        long[][] c = pow(b, n - 1);
        long result = 0;
        for (int i = 0; i <= 2 * k; i++)
            result = (result + c[2 * k][i]) % mod;
        out.println(result);
    }

    private InputReader in;
    private PrintWriter out;

    Task(InputReader in, PrintWriter out) {
        this.in = in;
        this.out = out;
    }
}

class InputReader {
    public BufferedReader reader;
    public StringTokenizer tokenizer;

    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream), 32768);
        tokenizer = null;
    }

    public String next() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public double nextDouble(){
        return Double.parseDouble(next());
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

    public long nextLong(){
        return Long.parseLong(next());
    }

    public byte nextByte(){
        return Byte.parseByte(next());
    }
}