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Problem 1433 Relation Ordering

Accept: 118    Submit: 265
Time Limit: 1000 mSec    Memory Limit : 32768 KB

Problem Description

There are 13 possible orderings for three numbers, if we sort them with the relation '<' and '=':
A = B = C , A = B < C , A < B = C ,A < B < C
A < C < B , A = C < B , B < A = C ,B < A < C
B < C < A , B = C < A , C < A = B ,C < A < B
C < B < A


Given an integer n, your task is to find the number of possible orderings for any n real numbers.

Input

There are several test cases. Each case contains only one integer n which is between 1 and 50.

Output

Output the number of different orderings for any n real numbers.

Sample Input

3

Sample Output

13

Source

FZU 2006 Summer Training II

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