重複字符串 找出 (10158)

D2=LEFT(B2,MODE(FIND(LEFT(B2,ROW($1:$9)),REPT(B2,9),ROW($1:$9)),2)-1)

另解{=LEFT(B2,MATCH(1=1,SUBSTITUTE(B2,LEFT(B2,ROW($1:9)),)="",))

另解{=LEFT(B2,MATCH("",SUBSTITUTE(B2,LEFT(B2,ROW($1:$99)),),))

另解{=IFERROR(LEFT(B2,MATCH(B2,REPT(LEFT(B2,ROW($1:99)),LEN(B2)/ROW($1:99)),)),LEFT(B2))

另解{=LEFT(B2,MATCH(1,FIND(B2,REPT(LEFT(B2,ROW($1:99)),99)),))