1 / 2, 1 / 4, 1 / 10, 1 / 26 () ()

1 / 2, 1 / 4, 1 / 10, 1 / 26 () ()


God, can you be serious? What a mess this is!



Find the rules: 2, 5, 10, () 26, 37, 50, () how to write?


Add 3,5,7,9,11,13 in turn
So fill in 10 + 7 = 17