n=k+1,(k+1)!<[(k+1)/2]^k(k+1)(k+1)!<2[(k+1)/2]^k+1因为:[(k+2)/(k+1)]^(k+1)=[1+1/(k+1)]^(k+1)>2,(k=1,2...) (怎么来的?凭空想出来的吗?)所以:(k+1)!<{[(k+1)+1]/2}^(k+1)