a(n) is the number of integers k less than 10^n such that the decimal representation of k lacks the digit 1,2,3, at least one of digits 4,5,6 and at least one of digits 7,8,9.
A126639
a(n) is the number of integers k less than 10^n such that the decimal representation of k lacks the digit 1,2,3, at least one of digits 4,5,6 and at least one of digits 7,8,9.
Terms
- a(0) =7a(1) =49a(2) =331a(3) =2137a(4) =13147a(5) =77449a(6) =440251a(7) =2432857a(8) =13151707a(9) =69895849a(10) =366600571a(11) =1903222777a(12) =9802234267a(13) =50171448649a(14) =255545887291
External references
- oeis: A126639