What will be the missing number?
The missing number is 122!
Solution is really simple. Look at the difference between first two numbers - it's 7. Difference between second and third number is 15 = 2 * 7 + 1 and between third and fourth number is 31 = 2 * 15 + 1.
So to get the missing number we have to add 2 * 31 + 1 = 63 to the last number.
59 + 63 = 122 - and this is the missing number