Enter your birth year: 2004
Enter your birth month [1-12]: 10
Enter your birth day [1-31]: 15

Your birthday day (Monday=0, Tuesday=1, etc.) is 4
Your birth year is a leap year = True

Your birth month calendar where Monday is the leftmost day:

    October 2004
Mo Tu We Th Fr Sa Su
             1  2  3
 4  5  6  7  8  9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30 31

Your birth month calendar where Sunday is the leftmost day:

    October 2004
Su Mo Tu We Th Fr Sa
                1  2
 3  4  5  6  7  8  9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31

The leap years from your birth year to 2023 are:

1. 2004
2. 2008
3. 2012
4. 2016
5. 2020