vladb,

I confused by the term 'DECIMAL DIGITS'. In the following sequence, I would count the number of decimal digits as:

   100                sum: 3
   101                sum: 6
   102                sum: 9
   ...
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In those 3 numbers, we have a total of 9 digits.

So if I use this code:

perl -E '$sum=0;for(1..1e6){$sum+=length($_);} say $sum;'
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The result printed as 5888896, which is not 27000001.

So how is the term 'DECIMAL DIGITS' defined? I think that is key to solving for the "real" answer.

Regards...Ed