Asking for help -- the problem of summation of arithmetic sequence Given that the tolerance of the arithmetic sequence {an} is 1, and a1 + A2 +... + A98 + A99 = 99, then the value of A3 + A6 + A9 +... + A99 is_____

Asking for help -- the problem of summation of arithmetic sequence Given that the tolerance of the arithmetic sequence {an} is 1, and a1 + A2 +... + A98 + A99 = 99, then the value of A3 + A6 + A9 +... + A99 is_____

(-46+50)*33/2=66