using System; using System.Collections.Generic; using System.Collections; using System.Collections.Specialized; using System.Linq; using System.Text; using System.IO; using System.Reflection; using static System.Math; using System.Numerics; //using nint=System.Int32; static class Program{ const int mod=(int)1e9+7; const double eps=1e-11; static void Main(){ Sc sc=new Sc(); var s=sc.Ia; int p=s[0]; Mint a=p+1,b=p-1; for(int i = 2;i<=s[1];i++) { Mint z=a+b+a*p+b; b=(a+b)*p*2-z; a=z; } Console.WriteLine("{0}",a); } } public struct Mint{ const int mod=(int)1e9+7; private long d; public Mint(long d){this.d=d;} public static implicit operator Mint(long d){return new Mint(d%mod);} public static explicit operator long(Mint d){return d.d;} public override string ToString(){return d.ToString();} public static Mint operator+(Mint a,long b){a.d=(a.d+b)%mod;return a;} public static Mint operator+(Mint a,Mint b){a.d=(a.d+b.d)%mod;return a;} public static Mint operator-(Mint a,long b){a.d=(mod+a.d-b)%mod;return a;} public static Mint operator-(Mint a,Mint b){a.d=(mod+a.d-b.d)%mod;return a;} public static Mint operator*(Mint a,long b){a.d=(a.d*b)%mod;return a;} public static Mint operator*(Mint a,Mint b){a.d=(a.d*b.d)%mod;return a;} public static Mint operator/(Mint a,long b){a.d=(a.d*Mi(b))%mod;return a;} public static Mint operator/(Mint a,Mint b){a.d=(a.d*Mi(b.d))%mod;return a;} private static long Mi(long a){ a=(a+mod)%mod; long b=mod,u=1,v=0; while(b>0){ long t=a/b; a-=t*b;a^=b;b^=a;a^=b; u-=t*v;u^=v;v^=u;u^=v; } u%=mod; if(u<0){u+=mod;} return u%mod; } } public class Sc{ public int I{get{return int.Parse(Console.ReadLine());}} public long L{get{return long.Parse(Console.ReadLine());}} public double D{get{return double.Parse(Console.ReadLine());}} public string S{get{return Console.ReadLine();}} public int[] Ia{get{return Array.ConvertAll(Console.ReadLine().Split(),int.Parse);}} public long[] La{get{return Array.ConvertAll(Console.ReadLine().Split(),long.Parse);}} public double[] Da{get{return Array.ConvertAll(Console.ReadLine().Split(),double.Parse);}} public string[] Sa{get{return Console.ReadLine().Split();}} public object[] Oa{get{return Console.ReadLine().Split();}} public int[] Ia2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),int.Parse);}} public int[] Ia3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),int.Parse);} public int[] Ia3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),int.Parse);} public long[] La2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),long.Parse);}} public long[] La3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),long.Parse);} public long[] La3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),long.Parse);} public double[] Da2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),double.Parse);}} public double[] Da3(int a){return Array.ConvertAll((a.ToString()+" "+Console.ReadLine()).Split(),double.Parse);} public double[] Da3(bool a,int b,bool c,int d){return Array.ConvertAll(((a?b.ToString()+" ":"")+Console.ReadLine()+(c?" "+d.ToString():"")).Split(),double.Parse);} public T[] Arr(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i