1/2+1/3+1/4+..,+1/63
=1/2+(1/3+1/4)+(1/5+1/6+1/7+1/8)+(1/9+1/10+...+1/16)+(1/17+1/18+...+1/32)+(1/33+1/34+...+1/63)
>1/2+(1/4+1/4)+(1/8+1/8+1/8+1/8)+(1/16+1/16+...+1/16)+(1/32+1/32+...+1/32)+(1/
( 8 phân số) ( 16 phân số)
63+1/63+...+1/63)
( 31 phân số)
>1/2+1/2+1/2+1/2+1/2+31/63
>2+1/2+31/63>2