a(n) = 2*(10^(2n+1)-1)/9 + 4*10^n.A332126a(n) = 2*(10^(2n+1)-1)/9 + 4*10^n.Terms a(0) =6a(1) =262a(2) =22622a(3) =2226222a(4) =222262222a(5) =22222622222External referencesoeis: A332126