#include <bits/stdc++.h>
#define F first
#define S second
using namespace std;
typedef long long ll;
ll powmod(ll a, ll p, ll modd) {
if (p==0) return 1;
if (p%2==0) {
a=powmod(a, p/2, modd);
return (a*a)%modd;
}
return (a*powmod(a, p-1, modd))%modd;
}
ll invp(ll a, ll p) {
return powmod(a, p - 2, p);
}
vector<ll> solve(vector<ll> S, ll mod) {
vector<ll> C = {1};
vector<ll> B = {1};
ll L = 0;ll m = 1;ll b = 1;ll N = S.size();
for (ll i = 0; i < N; i++) {
ll d = S[i];
for (ll j = 1; j <= L; j++) {
d += C[j]*S[i - j];d %= mod;
}
if (d == 0) {
m++;
} else if (2*L <= i) {
vector<ll> T = C;
ll a = (invp(b, mod)*d)%mod;
for (int j=0;j<i+1-2*L;j++) {
C.push_back(0);
}
L=i+1-L;
for (ll j = m; j <= L; j++) {
C[j] -= a*B[j - m];C[j] %= mod;
}
B = T;b = d;m = 1;
} else {
ll a = (invp(b, mod)*d)%mod;
for (ll j = m; j < m+(int)B.size(); j++) {
C[j] -= a*B[j - m];C[j] %= mod;
}
m++;
}
}
for (ll i = 0; i <= L; i++) {
C[i] += mod;C[i] %= mod;
}
return C;
}
struct LinearRecurrence {
vector<vector<ll> > mat;
vector<ll> seq;
ll mod;
vector<vector<ll> > mul(vector<vector<ll> > a, vector<vector<ll> > b) {
int n=a.size();
vector<vector<ll> > ret(n);
for (int i=0;i<n;i++){
ret[i].resize(n);
for (int j=0;j<n;j++){
ret[i][j]=0;
for (int k=0;k<n;k++){
ret[i][j]+=a[i][k]*b[k][j];
ret[i][j]%=mod;
}
}
}
return ret;
}
vector<vector<ll> > pot(vector<vector<ll> > m, ll p) {
if (p==1) return m;
if (p%2==0) {
m=pot(m, p/2);
return mul(m, m);
}
else {
return mul(m, pot(m, p-1));
}
}
ll get(ll index) {
if (index<(ll)mat.size()) {
return seq[index];
}
vector<vector<ll> > a=pot(mat, index-(ll)mat.size()+1);
ll v=0;
for (int i=0;i<(int)mat.size();i++) {
v+=a[0][i]*seq[(int)mat.size()-i-1];
v%=mod;
}
return v;
}
LinearRecurrence(vector<ll> S, ll mod_) {
seq=S;
mod=mod_;
vector<ll> C=solve(S, mod);
int n=C.size()-1;
mat.resize(n);
for (int i=0;i<n;i++) {
mat[i].resize(n);
}
for (int i=0;i<n;i++) {
mat[0][i]=(mod-C[i+1])%mod;
}
for (int i=1;i<n;i++) {
mat[i][i-1]=1;
}
}
};
const ll mod=1e9+7;
const int N=500;
ll dp[N+20][N+20][2];
struct FibonacciStringSum{
int get(int n, int a, int b){
dp[0][0][0]=1;
for (int i=0;i<N;i++){
for (int j=0;j<=i;j++){
for (int e=0;e<2;e++){
ll t=dp[i][j][e];
dp[i+1][j+1][0]+=t;
dp[i+1][j+1][0]%=mod;
if (e==0){
dp[i+1][j][1]+=t;
dp[i+1][j][1]%=mod;
}
}
}
}
vector<ll> ans;
for (int i=1;i<=N;i++){
ll t=0;
for (int j=0;j<=N;j++){
t+=(dp[i][j][0]+dp[i][j][1])*((powmod(j, a, mod)*powmod(i-j, b, mod))%mod);
t%=mod;
}
ans.push_back(t);
}
LinearRecurrence lr(ans, mod);
return lr.get(n-1);
}
};
int main(){
FibonacciStringSum fss;
int n, a, b;
cin>>n>>a>>b;
assert(n>=1&&n<=1000000000);
assert(0<=a&&a<=25);
assert(0<=b&&b<=25);
cout<<fss.get(n, a, b)<<endl;
}