PivotOJ

Stone Game

시간 제한: 1000ms메모리 제한: 512MB출처: USACO 2021 February GoldBOJ 21229

문제

Bessie and Elsie are playing a game with NN (1N1051\le N\le 10^5) piles of stones, where the ii-th pile has aia_i stones for each 1iN1\le i\le N (1ai1061\le a_i\le 10^6). The two cows alternate turns, with Bessie going first.

  • First, Bessie chooses some positive integer s1s_1 and removes s1s_1 stones from some pile with at least s1s_1 stones.
  • Then Elsie chooses some positive integer s2s_2 such that s1s_1 divides s2s_2 and removes s2s_2 stones from some pile with at least s2s_2 stones.
  • Then Bessie chooses some positive integer s3s_3 such that s2s_2 divides s3s_3 and removes s3s_3 stones from some pile with at least s3s_3 stones and so on.
  • In general, sis_i, the number of stones removed on turn ii, must divide si+1s_{i+1}.

The first cow who is unable to remove stones on her turn loses.

Compute the number of ways Bessie can remove stones on her first turn in order to guarantee a win (meaning that there exists a strategy such that Bessie wins regardless of what choices Elsie makes). Two ways of removing stones are considered to be different if they remove a different number of stones or they remove stones from different piles.

입력

The first line contains NN.

The second line contains NN space-separated integers a1,,aNa_1,\ldots,a_N.

출력

Print the number of ways Bessie can remove stones on her first turn in order to guarantee a win.

Note that the large size of integers involved in this problem may require the use of 64-bit integer data types (e.g., a "long long" in C/C++).

예제

예제 1

입력
1
7
출력
4

예제 2

입력
6
3 2 3 2 3 1
출력
8
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