#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
int c[110], b[110], sumb[110], sumc[110], f[110][11000];
signed main() {
  int n = 100, x;
  for (int i = 1; i <= n; i++) c[i] = 100;
  for (int i = 1; i < n; i++) b[i] = 100;
  for (int i = 1; i <= n; i++) sumc[i] = sumc[i - 1] + c[i];
  for (int i = 2; i <= n; i++) sumb[i] = sumb[i - 1] + b[i - 1];
  for (int i = 1; i <= n; i++) sumb[i] += sumb[i - 1];
  scanf("%*d%d", &x);
  for (int i = 0; i <= c[1]; i++) f[0][i] = 1;
  sumc[n + 1] = sumc[n];
  for (int i = 1; i <= n; i++) {
    for (int j = max(i * x + sumb[i], 0); j <= sumc[i]; j++)
      f[i][j] = (f[i - 1][j] -
                 (j - c[i] - 1 >= 0 ? f[i - 1][j - c[i] - 1] : 0) + mod) %
                mod;
    for (int j = 1; j <= sumc[i + 1]; j++)
      f[i][j] = (f[i][j] + f[i][j - 1]) % mod;
  }
  printf("%d\n", f[n][sumc[n + 1]]);
  return 0;
}
