using System;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Collections.Generic;
using System.Diagnostics;
using System.Numerics;
using Enu = System.Linq.Enumerable;
public class Program
{
static readonly int Mod = (int)1e9 + 7;
public void Solve()
{
int N = Reader.Int(), X = Reader.Int();
var C = new long[N + 1];
var Y = new long[N + 1];
for (int i = 1; i <= N; i++) C[i] = Y[i] = 1;
var ans = LinearRecurrenceRelation.Calc(C, Y, X, Mod);
Console.WriteLine(ans);
Console.ReadLine();
}
}
class LinearRecurrenceRelation
{
// F(n + 1) = C[0] + C[1] * Y(1) + C[2] * Y(2) + ... + C[n] * Y(n)
// return F(x)
public static long Calc(long[] C, long[] Y, long x, long mod)
{
if (x < Y.Length) return Y[x];
int N = C.Length;
var A = new ulong[C.Length];
for (int i = 0; i < C.Length; i++) A[i] = (ulong)C[i];
A = Power(A, x, (ulong)mod);
long res = 0;
for (int i = 0; i < C.Length; i++)
res = (res + (long)A[i] * Y[i]) % mod;
return res;
}
static ulong[] Power(ulong[] A, long p, ulong mod)
{
ulong[] x = new ulong[A.Length], res = new ulong[A.Length];
x[1] = res[0] = 1;
for (; p > 0; p >>= 1, x = Mult(x, x, A, mod))
if (p % 2 == 1) res = Mult(res, x, A, mod);
return res;
}
static ulong[] Mult(ulong[] A, ulong[] B, ulong[] C, ulong mod)
{
var res = new ulong[A.Length * 2];
for (int ai = 0; ai < A.Length; ai++)
for (int bi = 0; bi < B.Length; bi++)
{
res[ai + bi] += A[ai] * B[bi];
res[ai + bi] %= mod;
}
for (int x = res.Length - 1; x >= A.Length; x--)
for (int y = 0; y < C.Length; y++)
{
res[x - y - 1] += C[C.Length - y - 1] * res[x];
res[x - y - 1] %= mod;
}
var r = new ulong[A.Length];
Array.Copy(res, r, r.Length);
return r;
}
}
class Entry { static void Main() { new Program().Solve(); } }
class Reader
{
static TextReader reader = Console.In;
static readonly char[] separator = { ' ' };
static readonly StringSplitOptions op = StringSplitOptions.RemoveEmptyEntries;
static string[] A = new string[0];
static int i;
static void Init() { A = new string[0]; }
public static void Set(TextReader r) { reader = r; Init(); }
public static void Set(string file) { reader = new StreamReader(file); Init(); }
public static bool HasNext() { return CheckNext(); }
public static string String() { return Next(); }
public static int Int() { return int.Parse(Next()); }
public static long Long() { return long.Parse(Next()); }
public static double Double() { return double.Parse(Next()); }
public static int[] IntLine() { return Array.ConvertAll(Split(Line()), int.Parse); }
public static int[] IntArray(int N) { return Range(N, Int); }
public static int[][] IntTable(int H) { return Range(H, IntLine); }
public static string[] StringArray(int N) { return Range(N, Next); }
public static string[][] StringTable(int N) { return Range(N, () => Split(Line())); }
public static string Line() { return reader.ReadLine().Trim(); }
public static T[] Range<T>(int N, Func<T> f) { var r = new T[N]; for (int i = 0; i < N; r[i++] = f()) ; return r; }
static string[] Split(string s) { return s.Split(separator, op); }
static string Next() { CheckNext(); return A[i++]; }
static bool CheckNext()
{
if (i < A.Length) return true;
string line = reader.ReadLine();
if (line == null) return false;
if (line == "") return CheckNext();
A = Split(line);
i = 0;
return true;
}
}