#include <iostream>

#include <cstdio>

using namespace std;

FILE *f, *g;

int n, d;

int ap[6];

void readFile()
{
    f = fopen("pascal.in", "r");

    fscanf(f, "%d%d", &n, &d);

    fclose(f);
}

int solve235(int d)
{
    int i, rez = 0, x;

    for(i = 1; i < n; i ++)
    {
        x = n - i + 1;

        while(x % 2 == 0)
        {
            ap[2] ++;

            x /= 2;
        }

        while(x % 3 == 0)
        {
            ap[3] ++;

            x /= 3;
        }

        while(x % 5 == 0)
        {
            ap[5] ++;

            x /= 5;
        }

        x = i;

        while(x % 2 == 0)
        {
            ap[2] --;

            x /= 2;
        }

        while(x % 3 == 0)
        {
            ap[3] --;

            x /= 3;
        }

        while(x % 5 == 0)
        {
            ap[5] --;

            x /= 5;
        }

        if(ap[d] >= 1)
            rez ++;
    }

    return rez;
}

int solve4()
{
    int i, rez = 0, x;

    for(i = 1; i < n; i ++)
    {
        x = n - i + 1;

        while(x % 2 == 0)
        {
            ap[2] ++;

            x /= 2;
        }

        x = i;

        while(x % 2 == 0)
        {
            ap[2] --;

            x /= 2;
        }

        if(ap[2] >= 2)
            rez ++;
    }

    return rez;
}

int solve6()
{
    int i, rez = 0, x;

    for(i = 1; i < n; i ++)
    {
        x = n - i + 1;

        while(x % 2 == 0)
        {
            ap[2] ++;

            x /= 2;
        }

        while(x % 3 == 0)
        {
            ap[3] ++;

            x /= 3;
        }

        x = i;

        while(x % 2 == 0)
        {
            ap[2] --;

            x /= 2;
        }

        while(x % 3 == 0)
        {
            ap[3] --;

            x /= 3;
        }

        if(ap[2] >= 1 && ap[3] >= 1)
            rez ++;
    }

    return rez;
}

int rez;

void solve()
{
    int i;

    if(d == 2 || d == 3 || d == 5)
        rez = solve235(d);

    if(d == 4)
        rez = solve4();

    if(d == 6)
        rez = solve6();
}

void printFile()
{
    g = fopen("pascal.out", "w");

    fprintf(g, "%d\n", rez);

    fclose(g);
}

int main()
{
    readFile();

    solve();

    printFile();

    return 0;
}