On the wikipedia article http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week#Gauss.27_algorithm it explains the Gaussian Formula for calculating the first day of the year. I was wondering why the co-efficients are what they are. I understand the function, apart from this bit. Any help is appreciated.
Thanks In Advance!
Edit: I found this article: http://www.berndt-schwerdtfeger.de/bs/uploads/pdf/cal.pdf but I can't figure out the third and fourth coefficients now. It shows the calculation but not how it got there.