Gödel numbering for sequences

Gödel numbering is a way of taking any sequence of things--words, symbols, sentences, numbers, etc.-- and giving each one of them a special number. This number is what is called a Gödel number. Let's give an example using the word 'cat'. If we wanted to give the word "cat" a Gödel number, we would make a list of all the letters of the alphabet and give each one a special number. So 'a' might be 1, 'b' might be 2 and so on. Then we could give the word 'cat' the special number 3, 1, 20, or 3 for the letters c, a and t. Now 'cat' has a Gödel number!