import Foundation

let MAX_NUM: Int = 1000000
let SQRT_MAX = Int(sqrt(Double(MAX_NUM)))

var isPrime: [Bool] = Array(repeating: true, count: MAX_NUM+1)
(isPrime[0], isPrime[1]) = (false, false)

for n in 2...SQRT_MAX {
    if isPrime[n] {
        for i in stride(from: n*n, through: MAX_NUM, by: n) {
            isPrime[i] = false
        }
    }
}

func pairCount(_ num: Int) -> Int {
    var ans: Int = 0
    
    for n in 2...num/2 {
        if isPrime[n] && isPrime[num-n] {
            ans += 1
        }
    }
    
    return ans
}

func solve() -> [String] {
    var result: [String] = []
    guard let T = Int(readLine() ?? "") else { return []}
    
    for _ in 0..<T {
        guard let N = Int(readLine() ?? "") else { break }
        result.append(String(pairCount(N)))
    }
    
    return result
}

print(solve().joined(separator: "\n"))