#include <bits/stdc++.h>
using namespace std;
const int N = 2e5, M = 2e6, P = 6e6;
inline int gi() {
  char ch = getchar();
  int q = 0, x = 0;
  while (ch < '0' || ch > '9') q = (ch == '-' ? 1 : q), ch = getchar();
  while (ch >= '0' && ch <= '9') x = x * 10 + ch - '0', ch = getchar();
  return q ? (-x) : x;
}
int a[N], p[N][8], t[N], ans[M], L[M], dp[P][10], f[20];
vector<int> Q[N];
int main() {
  int n = gi(), q = gi(), s, op;
  for (int i = 1; i <= n; ++i) {
    s = gi();
    for (int j = 2; j * j <= s; ++j) {
      op = 0;
      while (s % j == 0) op ^= 1, s /= j;
      if (op) p[i][t[i]++] = j;
    }
    if (s > 1) p[i][t[i]++] = s;
  }
  for (int i = 1; i <= q; ++i)
    scanf("%d%d", &s, &op), Q[op].push_back(i), L[i] = s;
  for (int i = 1; i <= n; ++i) {
    for (int j = 0; j < (1 << t[i]); ++j) {
      int cnt = 0;
      s = 1;
      for (int k = 0; k < t[i]; ++k)
        if (j >> k & 1)
          s *= p[i][k];
        else
          ++cnt;
      for (int k = 0; k < 8; ++k) f[k + cnt] = max(f[k + cnt], dp[s][k]);
    }
    for (int j = 0; j < Q[i].size(); ++j)
      for (int k = 0; k < 16; ++k)
        if (f[k] >= L[Q[i][j]]) {
          ans[Q[i][j]] = k;
          break;
        }
    for (int j = 0; j < (1 << t[i]); ++j) {
      int cnt = 0;
      s = 1;
      for (int k = 0; k < t[i]; ++k)
        if (j >> k & 1)
          s *= p[i][k];
        else
          ++cnt;
      dp[s][cnt] = i;
    }
  }
  for (int i = 1; i <= q; ++i) printf("%d\n", ans[i]);
  return 0;
}
