Question

设N=（2+1）（2²+1）（2的4次方+1）（2的8次方+1）（2的16次方+1）,求N的各位数字,

Answer 1

原式=(2-1)(2+1)(2²+1)(2^4+1)(2^8+1)...(2^(2n)+1)+1

=(2²-1)(2²+1)(2^4+1)(2^8+1)...(2^(2n)+1)+1

=(2^4-1)(2^4+1)(2^8+1)...(2^(2n)+1)+1

=...

=2^(4n)-1+1;

=2^(4n)