#include // clang-format off using Int = long long; #define REP_(i, a_, b_, a, b, ...) for (Int i = (a), lim##i = (b); i < lim##i; i++) #define REP(i, ...) REP_(i, __VA_ARGS__, __VA_ARGS__, 0, __VA_ARGS__) struct SetupIO { SetupIO() { std::cin.tie(nullptr), std::ios::sync_with_stdio(false), std::cout << std::fixed << std::setprecision(13); } } setup_io; #ifndef _MY_DEBUG #define dump(...) #endif // clang-format on /** * author: knshnb * created: Fri Apr 24 21:54:06 JST 2020 **/ /// @docs src/DataStructure/SegmentTree.md template struct SegmentTree { const F op; const T e; SegmentTree(F op_, T e_) : op(op_), e(e_) {} int n; std::vector t; void set_by_identity(int n_) { n = n_; t.clear(), t.resize(2 * n, e); } void set_by_vector(const std::vector& a) { n = a.size(); t.clear(), t.resize(2 * n, e); for (int i = 0; i < n; i++) t[i + n] = a[i]; build(); } void build() { for (int i = n - 1; i; --i) t[i] = op(t[2 * i], t[2 * i + 1]); } T& operator[](int i) { return t[i + n]; } // [l, r) T query(int l, int r) const { assert(0 <= l && l <= r && r <= n); T resl = e, resr = e; for (l += n, r += n; l < r; l >>= 1, r >>= 1) { if (l & 1) resl = op(resl, t[l++]); if (r & 1) resr = op(t[--r], resr); } return op(resl, resr); } // i番目をxに変更 void update(int i, const T& x) { assert(0 <= i && i < n); t[i += n] = x; while (i >>= 1) t[i] = op(t[2 * i], t[2 * i + 1]); } // i番目にxを作用 (a[i] = op(a[i], x)) void operate(int i, const T& x) { assert(0 <= i && i < n); i += n; t[i] = op(t[i], x); while (i >>= 1) t[i] = op(t[2 * i], t[2 * i + 1]); } friend std::string to_string(const SegmentTree& seg) { return to_string(std::vector(seg.t.begin() + seg.n, seg.t.end())); } }; template auto make_segment_tree(F op, T e) { return SegmentTree(op, e); } signed main() { Int n; std::cin >> n; std::vector a(n); REP(i, n) std::cin >> a[i]; auto seg = make_segment_tree([](Int x, Int y) { return std::__gcd(x, y); }, 0LL); seg.set_by_vector(a); Int ans = 0; REP(i, n) { auto check = [&](Int mid) -> bool { return seg.query(i, mid + 1) == 1; }; Int ok = n, ng = i - 1; while (std::abs(ok - ng) > 1) { Int mid = (ok + ng) / 2; (check(mid) ? ok : ng) = mid; } ans += n - ok; } std::cout << ans << std::endl; }