充分性：设 ml4-A-m22a,“-a,=0 k0=1j=l 那么对每一对i,j都有 imaa0 (i=1,2,…,m;j=1,2,…,n) 即 lim d,=d (i=1,2,…,m;j=1,2,…,n) This docur t is produced by trial version of Print2Flash.Visit www.print2flash.com for more informationThis document is produced by trial version of Print2Flash. Visit www.print2flash.com for more information