#include <bits/stdc++.h>
using namespace std;
set<pair<long long, long long> > S;
set<pair<long long, long long> >::iterator it;
int n;
long long a[200005], ans;
pair<long long, long long> u;
void ins(pair<long long, long long> o) {
  it = S.upper_bound(pair<long long, long long>(o.first, -100));
  if (it != S.end() && it->first == o.first) {
    if (it->second < o.second) S.erase(it), S.insert(o);
  } else
    S.insert(o);
}
int main() {
  int i;
  scanf("%d", &n);
  for (i = 1; i <= n; i++) scanf("%I64d", &a[i]);
  S.insert(pair<long long, long long>(a[1], 0));
  for (i = 2; i <= n; i++) {
    while (S.size()) {
      it = S.end(), it--;
      if (it->first <= a[i]) break;
      u = (*it), S.erase(it);
      ins(pair<long long, long long>(
          a[i], u.second + (u.first / a[i] - 1) * (i - 1) * a[i]));
      if (u.first % a[i] != 0)
        ins(pair<long long, long long>(
            u.first % a[i], (u.first / a[i]) * (i - 1) * a[i] + u.second));
    }
  }
  while (S.size()) {
    it = S.begin();
    ans = max(ans, it->second + (it->first - 1) * n);
    S.erase(it);
  }
  cout << ans;
  return 0;
}
