Jon P. answered • 04/03/15
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Finding patterns can be very difficult. Sometimes there is more than one possibility.
In these numbers, there's no clear pattern in the values of the numbers, but I do see one pattern in how they are written.
If you ignore the commas, the sequence is 1 666 888 ?9 8
Maybe the pattern is that except for the first and last numbers, the digits come in sets of three. That would mean that the missing number is 99.
But it could be something else.
