a(n) = 8*(10^(2n+1)-1)/9 - 3*10^n.

A332185

a(n) = 8*(10^(2n+1)-1)/9 - 3*10^n.

Terms

    a(0) =5a(1) =858a(2) =88588a(3) =8885888a(4) =888858888a(5) =88888588888

External references