## Comment Re:Really? (Score 1) 189

A little thought reveals that any number in this sequence where the number you're adding to the end (n) is has a factor of 3 makes the whole number also divisible by 3. A little more thought reveals that where (n) has a factor of 3 the sequence of (n-1) will also have a factor of 3. This alone knocks out 2/3 of the possible numbers in the sequence that may be prime.