Using the digits 1-9, at most one time each, complete the first three terms of the arithmetic and geometric sequences.

What sequences result in the greatest sum of their second terms? (e.g. 3, 5, 7 and 2, 6, 18 would result in a sum of 5 +6 =11) Hint: There is more than one answer.

What sequences result in the least sum of their second terms? Hint: There is only one answer.