The last n digits of powers of 2 start cycling. a(n) is the number of zero-free terms in this cycle.
A181610
The last n digits of powers of 2 start cycling. a(n) is the number of zero-free terms in this cycle.
Terms
- a(0) =4a(1) =18a(2) =81a(3) =364a(4) =1638a(5) =7371a(6) =33170a(7) =149268a(8) =671701a(9) =3022653a(10) =13601945a(11) =61208743a(12) =275439346a(13) =1239477074a(14) =5577646830a(15) =25099410745a(16) =112947348510a(17) =508263067945
External references
- oeis: A181610