#include <bits/stdc++.h>
using namespace std;
const int twx = 1e4 + 100;
const int inf = 0x3f3f3f3f;
long long read() {
  long long sum = 0;
  long long flag = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') {
      flag = -1;
    }
    c = getchar();
  }
  while (c >= '0' && c <= '9') {
    sum = ((sum * 10) + c - '0');
    c = getchar();
  }
  return sum * flag;
}
long long n;
long long m;
long long k;
long long a[twx];
long long b[twx];
long long aa[twx];
long long ans;
long long lcm;
long long bg;
long long x, y;
long long gcd(long long x, long long y) { return !x ? y : gcd(y % x, x); }
long long mul(long long a, long long b, long long MOD) {
  long long s = 0;
  for (; b; b >>= 1, a = (a + a) % MOD) {
    if (b & 1) {
      s = (s + a) % MOD;
    }
  }
  return s;
}
long long exgcd(long long a, long long b, long long &x, long long &y) {
  if (!b) {
    x = 1;
    y = 0;
    return a;
  }
  long long gcd = exgcd(b, a % b, y, x);
  y -= a / b * x;
  return gcd;
}
long long china() {
  ans = a[1];
  lcm = b[1];
  for (int i = 2; i <= k; i++) {
    long long B = b[i];
    long long A = (a[i] - ans % B + B) % B;
    long long gcd = exgcd(lcm, B, x, y);
    long long bg = B / gcd;
    if (A % gcd) {
      return -1;
    }
    x = (x + bg) % bg;
    x = mul(x, A / gcd, bg);
    ans += x * lcm;
    lcm *= bg;
    ans %= lcm;
  }
  return ans == 0 ? lcm : ans;
}
void init() {
  n = read();
  m = read();
  k = read();
  if (k > m) {
    puts("NO");
    exit(0);
  }
  for (int i = 1; i <= k; i++) {
    aa[i] = read();
    b[i] = aa[i];
  }
}
void work() {
  for (int i = 1; i <= k; i++) {
    a[i] = (1 - i);
    while (a[i] < aa[i]) {
      a[i] += aa[i];
    }
    a[i] %= aa[i];
  }
  long long fuck = china();
  if (fuck == -1) {
    puts("NO");
    exit(0);
  }
  if (fuck + k - 1 > m) {
    puts("NO");
    exit(0);
  }
  if (lcm > n) {
    puts("NO");
    exit(0);
  }
  for (int i = 1; i <= k; i++) {
    if (gcd(lcm, fuck + i - 1) != aa[i]) {
      puts("NO");
      exit(0);
    }
  }
  puts("YES");
}
int main() {
  init();
  work();
  return 0;
}
