#include <bits/stdc++.h>

using namespace std;
typedef unsigned long long ull;

ull fact(int n)
{
    ull rez=1;
    for(int i=1 ;i<=n; ++i)
    {
        rez=rez*i;
    }
    return rez;
}
ull exp(ull x,int p)
{
    ull e=0, z=p;
    while(x/p){e=e+x/p;
    p*=z;}
    return e;
}


int main()
{
ifstream f("pascal.in");
ofstream g("pascal.out");
int r,d,p,div=0;;
f>>r>>d;
for(int i=0; i<=r; i++)
{
    if((exp(r,d)-exp(r-i,d)-exp(i,d))>=1) div++;

}
g<<div;


    return 0;
}