a(n) = 8*(10^(2n+1)-1)/9 - 7*10^n.

A332181

a(n) = 8*(10^(2n+1)-1)/9 - 7*10^n.

Terms

    a(0) =1a(1) =818a(2) =88188a(3) =8881888a(4) =888818888a(5) =88888188888

External references