9 + 99 + 999 + 9.999 +… + 9.999.999.999 = …

9 + 99 + 999 + 9.999 + 99.999 + 9.999.999.999 = 10.000.111.104

9 + 99 + 999 + 9.999 + 99.999 + 999.999+ 9.999.999 + 99.999.999 + 999.999.999+ 9.999.999.999 = 111112011