import math

def main():
    import sys
    input = sys.stdin.read
    data = input().split()
    T = int(data[0])
    a = 1.0 / (math.e * (math.pi ** 2))
    
    nodes = [
        -0.906179845938664,
        -0.538469310105683,
        0.0,
        0.538469310105683,
        0.906179845938664
    ]
    weights = [
        0.236926885056189,
        0.478628670499366,
        0.568888888888889,
        0.478628670499366,
        0.236926885056189
    ]
    
    results = []
    for i in range(1, T + 1):
        N = int(data[i])
        b = a / N
        if b == 0:
            integral = 0.0
        else:
            integral = 0.0
            for x, w in zip(nodes, weights):
                t = 0.5 * (x + 1) * b
                integral += w * math.exp(math.cos(t))
            integral *= 0.5 * b
        result = integral * N
        results.append("{0:.10f}".format(result))
    
    sys.stdout.write("\n".join(results) + "\n")

if __name__ == "__main__":
    main()