First of all, this may seem very basic for you, but I've never been good at math, and I can't figure this out!
I need to solve the number of sequences that exist under this conditions:
- All sequences are made of four numbers like 0123
- All the numbers must be different
- The first and the last number are on the same horizontal line
- The second and third numbers are on the horizontal line immediately above the first and last number line
This is table that is provided with the problem
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How many sequences exist under these conditions?