import math

if __name__ == "__main__":


    sfs_folded_hir = {0: 575935, 1: 346313, 2: 220539, 3: 130150, 4: 69989, 5: 33768, 6: 41031}

    n = len(sfs_folded_hir.values())
    pi = 0
    s_prime = 0
    for i in range(1, n-1):
        pi += i * (n-1) * sfs_folded_hir[i-1] / math.comb(n, 2)
        #s_prime +=  math.comb() * math.comb() / math.comb()


    print(pi)