#include <bits/stdc++.h>
using namespace std;
const int N = 2e5;
mt19937_64 rng(std::chrono::system_clock::now().time_since_epoch().count());
int n;
long long a[N], ans, val;
vector<int> v;
map<long long, long long> dp[N];
long long find(long long val) {
  int l = 0, r = v.size() - 1, bst = N;
  while (l <= r) {
    int mid = (l + r) / 2;
    if (a[v[mid]] > val)
      l = mid + 1;
    else {
      bst = v[mid];
      r = mid - 1;
    }
  }
  return bst;
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%lld", a + i);
    if (v.empty() || a[v.back()] > a[i]) v.push_back(i);
  }
  dp[0][a[0] - 1] = 0;
  for (int i = 0; i < n; i++)
    for (auto j : dp[i]) {
      int to = find(j.first);
      if (to == N) {
        ans = max(ans, j.second + n * j.first);
        continue;
      }
      long long is = j.first, sum = j.second;
      long long x = is / a[to] * a[to], rem = is % a[to];
      dp[to][rem] = max(dp[to][rem], sum + to * x);
      x -= a[to];
      rem = a[to] - 1;
      dp[to][rem] = max(dp[to][rem], sum + to * x);
    }
  printf("%lld\n", ans);
}
