Suppose I created the following random number generator.


A trusted person choose a irrational number. That can easily defined and computed by a computer. Like square root of a prime.


Every time the random number generator is called it calculate the first digit, then the second digit and it goes on.


On a given moment the random number generator is on digit N. An attacker saw the last M digits. (M < N)


Can you give me an example of a bad choice of irrational number that creates a pattern that is easy to guess some or all next numbers without knowing the number? (Only the last M digits is allowed to use in build the pattern)



Example of irrational number with a pattern in digits
$0.1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950\ldots$


