Blender model creates different format of 'f' records in exported .obj file

Question

I exported a model from blender to an obj and I want to use it for a game that I am making. The problem is that the format of the F in the obj file is different.

This is what my obj file contains:

f 48//1 210//1 212//1
f 75//2 219//2 209//2
f 51//3 7//3 52//3
f 7//4 53//4 52//4
f 53//5 11//5 54//5

I want my obj file to contain something like this:

f 1/1/1 37/2/1 3/3/1
f 3/3/2 39/4/2 5/5/2
f 5/5/3 40/6/3 7/7/3
f 7/8/4 41/9/4 9/10/4
f 41/9/5 11/11/5 9/10/5

Can somebody explain how to use this format or how to make Blender generate the face with the right format?

(sorry for the confusing title; please tell me better titles)

Answer 1

This was answered in the commentary by @scurest. In an .obj file, the second float in the slash-separated triple for each f face, represents the texture coordinate. If the object is not unwrapped, or it is exported without UV coordinates, the field will be empty.