a的三十二次方-1 =(a^16+1)(a^16-1) =(a^16+1)(a^8+1)(a^8-1) =(a^16+1)(a^8+1)(a^4+1)(a^4-1) =(a^16+1)(a^8+1)(a^4+1)(a^2+1)(a+1)(a-1)当a=2时,a的三十二次方-1可被10--20之间的15和17整除