多字元數字 計算為 7 整除 (15034)

C2=IF(MOD(SUMPRODUCT(MID(RIGHT(REPT(0,99)&B2,99),ROW($1:$33)*3-2,3)*-1^MOD(ROW($1:$33),2)),7),"","整除")

另解{=IF(MOD(SUM(MID(REPT(0,102-LEN(B2))&B2,ROW($1:$17)*6-{2,5},3)*{1,-1}),7),"","整除")