circa 1980 Casio with clock, similar to fx-8100

[xerxes]

(12-12-2018 06:17 PM)grsbanks Wrote:  NB: that trick doesn't work unless every year in the interval that's a multiple of 4 is a leap year.

The latest turn of the century was 2000, which was a leap year (multiple of 400) but 1900 was not and 2100 won't be!

Yes, the 28 years cycle will be disturbed in 2100, so we have to correct the calculators date from 1988 to 1976 on monday the 3-1-2100.