Numbers k such that the k-th triangular number contains only digits {1,4,7}.
A119127
Numbers k such that the k-th triangular number contains only digits {1,4,7}.
Terms
- a(0) =1a(1) =18a(2) =38a(3) =58a(4) =15306a(5) =28893a(6) =3851686a(7) =595216169886
External references
- oeis: A119127