(Science: day of the week) Zeller's congruence is an algorithm developed by Christian Zeller to calculate the day of the week. The formula is h=(q ⌊(26(m 1))/(10)⌋ k ⌊(k)/(4)⌋ ⌊(j)/(4)⌋ 5 j) % 7 where ∙h is the day of the week (0: Saturday, 1: Sunday, 2: Monday, 3: Tuesday, 4: Wednesday, 5: Thursday, 6: Friday). ∙q is the day of the month. ∙mis the month (3: March, 4: April, ...., 12: December). January and February are counted as months 13 and 14 of the previous year. ∙j is the century (i.e

Reflexive Property of Congruence | Overview, Proof & Examples