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

A332186

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

Terms

    a(0) =6a(1) =868a(2) =88688a(3) =8886888a(4) =888868888a(5) =88888688888

External references