Numbers k such that the k-th triangular number contains only digits {1,5,9}.
A119139
Numbers k such that the k-th triangular number contains only digits {1,5,9}.
Terms
- a(0) =1a(1) =5a(2) =10a(3) =13a(4) =34a(5) =101a(6) =109a(7) =138a(8) =1738a(9) =10114a(10) =19794a(11) =1011090a(12) =1019010a(13) =1054130a(14) =1091010a(15) =34406858a(16) =178858133a(17) =565606858
External references
- oeis: A119139