Partial sums of A051109.

Terms

a(0) =1a(1) =3a(2) =8a(3) =18a(4) =38a(5) =88a(6) =188a(7) =388a(8) =888a(9) =1888a(10) =3888a(11) =8888a(12) =18888a(13) =38888a(14) =88888a(15) =188888a(16) =388888a(17) =888888a(18) =1888888a(19) =3888888a(20) =8888888a(21) =18888888a(22) =38888888a(23) =88888888a(24) =188888888a(25) =388888888a(26) =888888888a(27) =1888888888a(28) =3888888888a(29) =8888888888