How many natural numbers can be taken from 1, 2, 3, 2004, 2005 at most, and the difference between each two numbers is not equal to 4

How many natural numbers can be taken from 1, 2, 3, 2004, 2005 at most, and the difference between each two numbers is not equal to 4

Find the rule: 1,2,3,4,5 these five numbers, you can take 1,2,3,4 or 2,3,4,5 at most
From this, we can see that if we take four consecutive numbers, then empty the four consecutive numbers and cycle in turn, we can meet the requirements
But how much do you start with? 1? 2? 3? Or something else
Starting from 1, 1004 can be taken
Starting from 2, 1004 can be taken
Starting from 3, 1003 can be taken
From four, 1000
Starting from 5, 1001
Starting from 6, 1001
Up to 1004