#include <cstdio>

#include <cstring>

#include <algorithm>

using namespace std;

struct inum {

	static const int N=205, MOD=10000;

	int a[N], len;

	inum(int x=0) { len=!x; memset(a, 0, sizeof a); while(x) a[++len]=x%MOD, x/=MOD; }

	void fix() { while(len>1 && !a[len]) --len; }

	void cln() { memset(a, 0, sizeof(int)*(len+1)); len=1; }

	const bool operator<= (const inum &x) {

		if(len<x.len) return 1;

		if(len>x.len) return 0;

		for(int i=len; i; --i)

			if(a[i]<x.a[i]) return 1;

			else if(a[i]>x.a[i]) return 0;

		return 1;

	}

	inum operator+ (const inum &x) {

		static inum ret;

		ret.cln();

		ret.len=max(len, x.len);

		for(int i=1; i<=ret.len; ++i) {

			ret.a[i]+=a[i]+x.a[i];

			if(ret.a[i]>=MOD) ret.a[i+1]+=ret.a[i]/MOD, ret.a[i]%=MOD;

		}

		ret.len++;

		ret.fix();

		return ret;

	}

	inum operator- (const inum &x) {

		static inum ret;

		ret.cln();

		for(int i=1; i<=len; ++i) {

			ret.a[i]+=a[i]-x.a[i];

			if(ret.a[i]<0) --ret.a[i+1], ret.a[i]+=MOD;

		}

		ret.len=len;

		ret.fix();

		return ret;

	}

	inum operator* (const inum &x) {

		static inum ret;

		ret.cln();

		for(int i=1; i<=len; ++i)

			for(int j=1; j<=x.len; ++j) {

				ret.a[i+j-1]+=a[i]*x.a[j];

				if(ret.a[i+j-1]>=MOD) ret.a[i+j]+=ret.a[i+j-1]/MOD, ret.a[i+j-1]%=MOD;

			}

		ret.len=len+x.len;

		for(int i=1; i<=ret.len; ++i)

			if(ret.a[i]>=MOD) ret.a[i+1]+=ret.a[i]/MOD, ret.a[i]%=MOD;

		ret.fix();

		return ret;

	}

	inum div2() {

		static inum ret;

		ret.cln();

		for(int i=len, t=0; i; --i) {

			t+=a[i];

			ret.a[i]=t>>1;

			t=(t&1)*MOD;

		}

		ret.len=len;

		ret.fix();

		return ret;

	}

	inum operator/ (const inum &x) {

		static inum l, r, mid, ONE(1);

		l=0; r=*this;

		while(l<=r) {

			mid=(l+r).div2();

			if(mid*x<=*this) l=mid+ONE;

			else r=mid-ONE;

		}

		return l-ONE;

	}

	inum operator% (const inum &x) { return *this-(*this/x)*x; }

	static inum gcd(inum a, inum b) { return (b.len==1&&!b.a[1])?a:gcd(b, a%b); }

	static inum pow(inum a, int n) {

		inum x=1;

		while(n) { if(n&1) x=x*a; a=a*a; n>>=1; }

		return x;

	}

	void P() {

		printf("%d", a[len]);

		for(int i=len-1; i; --i)

			printf("%.04d", a[i]);

	}

};

const int N=105;

inum C[N][N], d[N][N];

int n, m, l;

int main() {

	C[0][0]=1;

	for(int i=1; i<=100; ++i) {

		C[i][0]=1;

		for(int j=1; j<=i; ++j)

			C[i][j]=C[i-1][j-1]+C[i-1][j];

	}

	while(~scanf("%d%d%d", &m, &n, &l)) {

		if(l>m) { puts("mukyu~"); continue; }

		d[0][0]=1; --l;

		for(int i=1; i<=n; ++i)

			for(int j=1; j<=m; ++j) {

				d[i][j]=0; int t=min(j, l);

				for(int k=0; k<=t; ++k)

					d[i][j]=d[i][j]+d[i-1][j-k]*C[m-(j-k)][k];

			}

		inum up=0, down=0, gcd;

		for(int i=1; i<=n; ++i) up=up+d[i][m];

		down=inum::pow(n, m);

		up=down-up;

		gcd=inum::gcd(up, down);

		down=down/gcd;

		up=up/gcd;

		up.P(); putchar('/'); down.P(); puts("");

	}

	return 0;

}