Lasse's Solution
xy
xx
xyx
xxx
xyxx
"x" and "y" each represents a number.
Find out the system to make the next line
Explanation:
x = 1, y = 0
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10
11
101
111
1011
Each line now represents a number in the binary system.
-----------
Convert these numbers into our own 0-9system and you get:
2
3
5
7
11
Primary numbers
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Next prime is 13
13 in binary is: 1101
Therefor, the next line is: xxyx
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If it's not possible to solve the puzzle without more information,
can you try if it's possible if another textline is added ?
I mean:
xy
xx
xyx
xxx
xyxx
xxyx
and then the solver should try and find
xyyyx (17)