I know the answer for mystery(4) is : 1, 2, 4, but how?

Can anyone explain? thanks

O BJP4 Self-Check 12.3: mystery1 Favorit Language/Type: Java recursion recursive tracing Whitaker Brand (on 2016/09/08) Author: For each call to the following method, indicate what console output is produced public void mystery1 (int n) { System.out.print(n); } else ( mystery1(n / 2); System.out.print(", " + n); mystery1(1); mystery1 (4); mystery1(16); mystery1(30); mystery1(100); , 4, 21 Submt O You passed 1 of 5 tests. Try agairn result pass fail question your answer 1 1mystery1(1); 2mystery1 (4); , 4, 21