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January 1, 1901 was a
Tuesday

How to solve: January 1, 1901

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 121 ÷ 12→0
    Practice →
  3. 3
    Remainder of 121 % 12→1
    Practice →
  4. 4
    Divide remainder by 41 ÷ 4→0
    Practice →
  5. 5
    Year's doomsday(3 + 0 + 1 + 0) % 7→4 → Thursday
    Practice →
  6. 6
    Month doomsdayJanuary→3rd
    Practice →
  7. 7
    Distance1 − 3→-2
    Practice →
  8. 8
    Final answer(4 + -2) % 7→2 → Tuesday
Practice the Doomsday algorithm →