2派等于6.28,三派等于9.42,四派等于12.56,五派等于15.7,六派等于18.84,七派等于21.98八派等于25.12
2兀=6·28 3兀=9.42 4兀=12.56
6.289.4212.5615.718.8421.9825.1228.26
6.28 9.4212.5615.718.8421.9825.1228.2631.4