参考百度,】an=2n,即2 4 6 8 10 12 14 16 a1a2+…+anan+1=An,即8 24 48 80 120 168 ……An=4n(n+1)平方和的公式为S＝n(n+1)(2n+1)/6所以,Sn＝4×n(n+1)(2n+1)/6＋4×n(n+1)/2＝2n(n+1)(2n+1)/3＋2n(n+1)＝2n(n+1)(2n...