6741.Two Sets II

Time Limit: 1s Memory Limit: 512MB

Your task is to count the number of ways numbers $1,2,\ldots,n$ can be divided into two sets of equal sum.

For example, if $n=7$ , there are four solutions:

  • ${1,3,4,6}$ and ${2,5,7}$
  • ${1,2,5,6}$ and ${3,4,7}$
  • ${1,2,4,7}$ and ${3,5,6}$
  • ${1,6,7}$ and ${2,3,4,5}$

Input Format(From the terminal/stdin)

The only input line contains an integer $n$ .

  • $1 \le n \le 500$

Output Format(To the terminal/stdout)

Print the answer modulo $10^9+7$ .

Sample Input

Copy
7
 \n

Sample Output

Copy
4
 \n
Source: CSES, Dynamic Programming, 1093

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