Number of n-digit numbers that are divisible by 5^n.

Terms

a(0) =1a(1) =3a(2) =7a(3) =14a(4) =28a(5) =57a(6) =115a(7) =230a(8) =460a(9) =921a(10) =1843a(11) =3686a(12) =7372a(13) =14745a(14) =29491a(15) =58982a(16) =117964a(17) =235929a(18) =471859a(19) =943718a(20) =1887436a(21) =3774873a(22) =7549747a(23) =15099494a(24) =30198988a(25) =60397977a(26) =120795955a(27) =241591910a(28) =483183820a(29) =966367641