找规律,当num = 6 那么就是 6*5 + 1 ,33 ,35, 37 ,39 ,41 (num个数相加)

while True:
    try:
        num = int(input())
        target = num * (num - 1) + 1
        b = []
        for i in range(num):
            b.append(target)
            target += 2
        for i in range(len(b)):
            b[i] = str(b[i])
        print('+'.join(b))
    except:
        break