Triangular-Type Selfie Numbers

Numbers represented by their own digits by certain operations are considered as selfie numbers. There are many ways of writing selfie numbers, such as, numbers written in digit's order or its reverse just with basic operations. We can extend them by use of other operations, such as, factorial, square-root, Triangular numbers, Fibonacci sequence values, etc. In this work, the selfie numbers are written by use of triangular numbers in digit's order and reverse