First line is: [Sequence length] ENERGY = [ENERGY] Structure name
Then there are [Sequence length] lines is the following format:
[Base number] [BASE] [Previous base number] [Next base number] [Link] [Base number]
Exemple:

10 ENERGY = 0 RNAExample
1 A 0 2 0 1
2 A 1 3 9 2
3 C 2 4 8 3
4 C 3 5 7 4
5 U 4 6 0 5
6 U 5 7 0 6
7 G 6 8 4 7
8 G 7 9 3 8
9 U 8 10 2 9
10 G 9 11 0 10