README.md

Sweep Rowing

A sweep rowing is a type of academic rowing where each athlete paddles with one oar to the left or the right of the boat. The rowing team consists of $2 n$ athletes numbered from 1 to $2 n$ in the order in which they sit in the boat. The ideal placement of rowers must meet two conditions:

1. the number of athletes rowing on the left (L-rowers) should be the same as the number of athletes rowing on the right (R-rowers);
2. the sum of the numbers of L-rowers should be equal to the sum of the numbers of R-rowers.

For example, if $n=2$, arrangements LRRL and RLLR are ideal, whereas arrangements LRRR and RLRL are not.

Your task is to find the number of ideal arrangements for a given $n$. Since this number can be large, print it modulo $10^9+7$.

Input Format

The input contains one integer $n$.

Constraints

$1 \le n \le 250.$

Output Format

Print the number of different ideal arrangements modulo $10^9+7$.

Sample Input 1

1

Sample Output 1

0

Sample Input 2

2

Sample Output 2

2