The number of integers k less than 2^n whose decimal representation of their reciprocals has an odd period.

A284904

The number of integers k less than 2^n whose decimal representation of their reciprocals has an odd period.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =2a(4) =5a(5) =10a(6) =20a(7) =40a(8) =80a(9) =150a(10) =280a(11) =522a(12) =965a(13) =1802a(14) =3393a(15) =6426a(16) =12197a(17) =23236a(18) =44419a(19) =85116a(20) =163543a(21) =314837a(22) =607440a(23) =1174134a(24) =2273619a(25) =4409116a(26) =8561931a(27) =16646790a(28) =32404446a(29) =63145533

External references