(49G) Friday 13th calculation

[Joe Horn]

(06-24-2014 02:05 PM)Alberto Candel Wrote:  Those are pretty. Some time ago I read somewhere, I forget where, that over the years, the most frequent day for a 13th was a Friday, or the other way around. It should be easy to verify with these programs. Good for a coffe break.

Unless my User RPL has bugs, you're right. The calendar repeats exactly every four centuries, so all we need to do is tally all 4800 13ths from 2000 through 2399. Here's what I got:

684 Thursdays & Saturdays
685 Mondays & Tuesdays
687 Sundays & Wednesdays
688 Fridays!