Question

What is the next value 1I2L3F4

Answer 1

The given terms can be divided into two sections. First section is for the numbers and the second one for the letters.

1st section:    1, 2, 3, and 4
2nd section:    I, L, F


I is the 9th letter in the alphabet, L is the 12th letter, and F is the 6th letter in the alphabet. 

The pattern observed:
                    I to L:    12 - 9 = 3
                    L to F:    6 - 12 = -6

Next letter should be +9. This means that the letter should be 9 places higher than F. The letter should be O which is the 15th letter.