Hello, Xsi, This has already been much discussed... If you want to express a general fact, you'll say "I like looking at pages of codes", but drop the 20, it means "one of my favourite occupations is looking at pages of codes" (not "at 20 pages of codes"). Then you can also say: "I like to look at these 20 pages of codes", which is not general, because you refer to the 20 pages of codes you may have right in front of you.
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