Numbers n such that the cardinality of (natural numbers <=n with a first digit of 1) = n/2.
A228158
Numbers n such that the cardinality of (natural numbers <=n with a first digit of 1) = n/2.
Terms
- a(0) =2a(1) =16a(2) =22a(3) =176a(4) =222a(5) =1776a(6) =2222a(7) =17776a(8) =22222a(9) =177776a(10) =222222a(11) =1777776a(12) =2222222a(13) =17777776a(14) =22222222a(15) =177777776a(16) =222222222a(17) =1777777776a(18) =2222222222a(19) =17777777776a(20) =22222222222a(21) =177777777776a(22) =222222222222
External references
- oeis: A228158