The formula that must be memorized on the first day of the month is as follows: C in the year of Jia and Ji is the head, and Wu in the year of Yi and Geng is the head. Bingxin will definitely seek Geng's rise, and Ding Renren will move forward. If you ask where Wugui comes from. Those above Jiayin are easy to pursue.
In a year when the Heavenly Stem is A or Ji, the Heavenly Stem of the first month is C, then the second month from the beginning is Ding, and the third month is Wu... The following sentences are the same as the same period. Ding and Renren are in direct flow, that is, in the celestial stem year when Ding or Ren is encountered, the first month starts from Ren. If you ask where Wu Gui will come from, it is easy to pursue Jia Yin. In other words, in the year of Wu or Gui, the stem and branch of the first month are Jiayin, because the earthly branch of the first month is Yin.
The first day of the month method
There are twelve months in a year, and the average number of days is 365 days. Regardless of the fact that leap years have one more day than ordinary years, just considering 365 days, you can already find that the relationship between the sun and the month is not so clear and clear.
Let’s calculate the thirty days in a month. Divide three hundred and sixty-five by thirty, and you get twelve more than five. This means that even if there are only 365 days in a year, and the number of days in each month is 30, the 365 days cannot be evenly distributed in the twelve months of the year. There are only five days It always stands out. The combination of heavenly stems and earthly branches takes sixty as a rotation cycle, sixty is twice thirty, and five times twelve is sixty.
Even if there are only 365 days in a year, the extra five days will take twelve years to form a Jiazi cycle. If factors such as leap years and the difference in the number of days between large and small months are also taken into account, the relationship between the month and the day becomes even more complicated.