a(n) = 10^(2*n+1) - 4*10^n - 1.

A332195

a(n) = 10^(2*n+1) - 4*10^n - 1.

Terms

    a(0) =5a(1) =959a(2) =99599a(3) =9995999a(4) =999959999a(5) =99999599999

External references