- * less than the square root of the number of states, or 2**4121 (4.67E+1240).
- * [Auma06] reveals a large set of weak states, consisting of those for which
- * the first value is repeated one or more times elsewhere in the state
- * vector.
- * These induce a bias in the output relative to the repeated value.
- * The seed values used as input below are scrambled before being used, so any
- * duplicates in them do not imply duplicates in the resulting internal state,
- * however the chances of some duplicate existing elsewhere in a random state
- * are just over 255/2**32, or merely 1 in 16 million.
- * Such states are, of course, much rarer in ISAAC-64.
- * It is not clear if an attacker can tell from just the output if ISAAC is in
- * a weak state, or deduce the full internal state in any case except that
- * where all or almost all of the entries in the state vector are identical.