#include using namespace std; inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;} template inline string toString(T x) {ostringstream sout;sout< VI; typedef vector VVI; typedef vector VS; typedef pair P; typedef tuple tpl; #define ALL(a) (a).begin(),(a).end() #define RALL(a) (a).rbegin(), (a).rend() #define SORT(c) sort((c).begin(),(c).end()) #define REVERSE(c) reverse((c).begin(),(c).end()) #define LB(a,x) lower_bound((a).begin(), (a).end(), x) - (a).begin() #define UB(a,x) upper_bound((a).begin(), (a).end(), x) - (a).begin() #define FOR(i,a,b) for(int i=(a);i<(b);++i) #define REP(i,n) FOR(i,0,n) #define RFOR(i,a,b) for(int i=(a)-1;i>=(b);--i) #define RREP(i,n) RFOR(i,n,0) #define en "\n" const double EPS = 1e-9; const double PI = acos(-1.0); const int INT_INF = 2147483647; const long long LL_INF = 1LL<<60; const long long MOD = 1000000007; #define CLR(a) memset((a), 0, sizeof(a)) #define dump(x) cerr << #x << " = " << (x) << endl; #define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } struct mint { long long x; mint(long long x=0):x((x%MOD+MOD)%MOD){} mint operator-() const { return mint(-x);} mint& operator+=(const mint a) { if ((x += a.x) >= MOD) x -= MOD; return *this; } mint& operator-=(const mint a) { if ((x += MOD-a.x) >= MOD) x -= MOD; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= MOD; return *this; } mint operator+(const mint a) const { mint res(*this); return res+=a; } mint operator-(const mint a) const { mint res(*this); return res-=a; } mint operator*(const mint a) const { mint res(*this); return res*=a; } mint pow(long long t) const { if (!t) return 1; mint a = pow(t>>1); a *= a; if (t&1) a *= *this; return a; } // for prime MOD mint inv() const { return pow(MOD-2); } mint& operator/=(const mint a) { return (*this) *= a.inv(); } mint operator/(const mint a) const { mint res(*this); return res/=a; } }; int main(void){ ll N,d,K; cin >> N >> d >> K; mint dp[N+1][K+2]; dp[0][0] = 1; dp[0][1] = -1; mint imos = 0; REP(i,N){ imos = 0; REP(j,K){ imos += dp[i][j]; if(imos.x > 0){ dp[i+1][j+1] += imos; dp[i+1][min(K+1,j+d+1)] -= imos; } } } imos = 0; REP(i,K) imos += dp[N][i+1]; cout << imos.x << en; return 0; }