Single Digit Representations of Natural Numbers From 10001 to 15000

There are different ways of representing natural numbers, such as writing in terms of 1 to 9 or 9 to 1, writing in terms of single letter, single digit, flexible power, etc. These types of representations we call as crazy representations. This paper bring numbers 10001 to 15000 in terms of each digit. The total work up to 20000 numbers divided in four parts. For other parts can be seen in reference list.