SOLUTION: If the nth term is 3n-1 then why isn't 85 a term in the sequence

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Question 875615: If the nth term is 3n-1 then why isn't 85 a term in the sequence
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
If 85 was a term of the sequence, then for some integer n, 3n - 1 = 85 <--> n = 86/3 which is not an integer. Hence 85 is not in the sequence.

A more formal and concise way of putting it is the sequence consists only of numbers congruent to 2 modulo 3; 85 is 1 modulo 3.