a(n) = 20*a(n-1) - a(n-2), starting with a(0) = 2 and a(1) = 20.

A090728

a(n) = 20*a(n-1) - a(n-2), starting with a(0) = 2 and a(1) = 20.

Terms

    a(0) =2a(1) =20a(2) =398a(3) =7940a(4) =158402a(5) =3160100a(6) =63043598a(7) =1257711860a(8) =25091193602a(9) =500566160180

External references