Question

What's the explicit formula for the sequence :")

Answer 1

Hello from MrBillDoesMath!

Answer:

a(n) = 12 - 3(n-1)          , n = 1,2,3.,,

Discussion:

The terms are 12, 9, 6, 3  so we are apparently subtracting 3 from each succeeding term. . Hence

a(n) = 12 - 3(n-1)          , n = 1,2,3.,,

Thank you,

MrB