原式=2(3+1)(3二次+1)(3四次+1)...(3三十二次+1)/2-3六十四次/2 =(3-1)(3+1)(3二次+1)(3四次+1)...(3三十二次+1)/2-3六十四次/2 =(3二次-1)(3二次+1)(3四次+1)...(3三十二次+1)/2-3六十四次/2 =(3四次-1)(3四次+1).....