#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;
}