import math


def loggam(x):
        # double x0, x2, xp, gl, gl0;
        # long k, n;

        a = [8.333333333333333e-02, -2.777777777777778e-03,
             7.936507936507937e-04, -5.952380952380952e-04,
             8.417508417508418e-04, -1.917526917526918e-03,
             6.410256410256410e-03, -2.955065359477124e-02,
             1.796443723688307e-01, -1.39243221690590e+00]
        x *= 1.0
        x0 = x
        n = 0
        if x == 1.0 or x == 2.0:
            return 0.0

        elif x <= 7.0:
            n = int(7 - x)
            x0 = x + n
        x2 = 1.0 / (x0*x0)
        xp = 2 * math.pi
        gl0 = a[9]
        for k in range(8, -1, -1):
            gl0 *= x2
            gl0 += a[k]
        gl = gl0/x0 + 0.5 * math.log(xp) + (x0-0.5) * math.log(x0) - x0
        if x <= 7.0:
            for k in range(1, n + 1):
                gl -= math.log(x0-1.0)
                x0 -= 1.0
        return gl

print(loggam(2))
print(loggam(3))
print(loggam(4))
print(loggam(5))