# What day of the week is Jan 1st 1,000,000AD ?

Discussion in 'Computer Support' started by Trevor Smith, Nov 4, 2003.

1. ### Trent CGuest

There is nothing wrong with the "formula"...
Well spotted, Ralph!

OK, the rules say that a leap century only happens when the year is
divisible by 400, so 1996 and 2000 were leap years, but not 97, 98 and 99.
So we have 25 leap century years per 1,000 years, 25,000 in 1,000,000 and
for our calculation, 24,950 (we're starting the count at the year 2000 not 0
and we remove 2 millennia-worth - 50).

That makes our total after division 52,006,492.85. A thought, though: does
your earlier decimal formula account for a starting day of Saturday for Jan
1st 2000?

Trent C, Nov 5, 2003

2. ### anthonyberetGuest

Ralph Mann wrote:
How do you know how many days are involved?
--
Put "usenet" in the subject-line if you want to mail me, otherwise it will
be spam-filtered.
Do you use filesharing networks? If so, please visit my online poll:
http://vote.sparklit.com/web_poll.spark/780772
anthonyberet

anthonyberet, Nov 5, 2003

3. ### anthonyberetGuest

I think you need to drop the word "else" from your post.
--
Put "usenet" in the subject-line if you want to mail me, otherwise it will
be spam-filtered.
Do you use filesharing networks? If so, please visit my online poll:
http://vote.sparklit.com/web_poll.spark/780772
anthonyberet

anthonyberet, Nov 5, 2003
4. ### Ralph MannGuest

Trent C said:
Er, no it calculates based on the very first week day being Monday.
If you are going to use Saturday as *your* starting point, then my formula would
be used with Saturday as the first day.

Ralph Mann, Nov 5, 2003
5. ### anthonyberetGuest

Ralph Mann wrote:
Yes there is.
--
Put "usenet" in the subject-line if you want to mail me, otherwise it will
be spam-filtered.
Do you use filesharing networks? If so, please visit my online poll:
http://vote.sparklit.com/web_poll.spark/780772
anthonyberet

anthonyberet, Nov 5, 2003
6. ### Ralph MannGuest

anthonyberet said:
Involved in what?
The total number of elapsed days, or the number of days in a week?

Ralph Mann, Nov 5, 2003
7. ### Ralph MannGuest

anthonyberet said:

Ralph Mann, Nov 5, 2003
8. ### Ralph MannGuest

Ralph Mann said:
I must add here that you are out by 2 days according to this
http://www.geocities.com/eu84/frtop_files/calendar.htm
as your calculation comes up with Thursday.

Ralph Mann, Nov 5, 2003
9. ### Ralph MannGuest

anthonyberet said:
Whatever.

Ralph Mann, Nov 5, 2003
10. ### Ralph MannGuest

Ralph Mann said:
Actually, if you stay with using Monday as the first day and not Saturday, your
calculation is correct, and the day shows as Saturday as per the above link.

Ralph Mann, Nov 5, 2003
11. ### Trent CGuest

There is nothing wrong with the "formula"...
Righto, that makes my earlier suggestion of Friday wrong on two counts (any
more offers?)! To quote your decimal formula and add the alteration for a
Jan 1st 2000 startpoint:
..142857142 = Monday Saturday
..285714285 = Tuesday Sunday
..428571428 = Wednesday Monday
..571428571 = Thursday Tuesday
..714285714 = Friday Wednesday
..857142857 = Saturday Thursday
..0 = Sunday Friday

This now suggests Thursday as an answer. Ralph, you seem to be the only
person who's actually looking at the formula - what do you think?

Trent C, Nov 5, 2003
12. ### Ralph MannGuest

Trent C said:
See my last post to you, as if you continue to use Monday as the first day of
the week, your calculation arrives at Saturday which is correct according to the
link I gave in that same post.

Ralph Mann, Nov 5, 2003
13. ### Trent CGuest

I calculated on the basis of a 365 day year, and a leap year of
every 4
Hang on Ralph, did I miss something? If you look at the decimal formula I
copied from your earlier post, you'll see I added a new set of days,
starting on Saturday, thus my final calculation, with a decimal of .85,
suggests Thursday.

Trent C, Nov 5, 2003
14. ### Ralph MannGuest

Trent C said:
You don't need to remove 50 here, as you aren't using the first 1999 years in
your calculation, however you need to add 1 as you are using 2000 as a starting
point, but then again, I don't remember 2000 actually getting that extra day to
make it a 367 day year.

Ralph Mann, Nov 5, 2003
15. ### Ralph MannGuest

Ralph Mann said:
Er, 2 because 2000 was also a leap year.

Ralph Mann, Nov 5, 2003
16. ### Trent CGuest

There is nothing wrong with the "formula"...
Surely, though, since we're basing our calculations on 1,000,000 years, and
we're starting at AD 2000, we have to allow for those years somewhere, don't
we?

And the year 2000 had 366 years - a full leap year - unlike 1900, 1800 and
1700 (please ignore my error in the earlier post).

Oh god, my head's beginning to hurt!

Trent C, Nov 5, 2003
17. ### Ralph MannGuest

Trent C said:

No, because you are leaving them out of the calculation and using Sat 1 Jan 2000
as day 1.
And yes, as Saturday would be the first day of the week, then your change to the
decimal correlation would be correct.
I am only getting confused by the distinction/inclusion of a leap year and a
leap century.
Every 4th year from 2000 would have an extra day, and every century divisible by
400 would also have an extra day.
Based on that, years like 2000, 2400, 2800 etc would have 2 extra days, 1 for
the 4 year cycle and 1 for the 400 year cycle.

Ralph Mann, Nov 5, 2003
18. ### Trent CGuest

Trent C, Nov 5, 2003
19. ### Ralph MannGuest

Trent C said:
Just goes to show how those using fancy methods can screw it up and get away
with it ;-)

Ralph Mann, Nov 5, 2003
20. ### Trent CGuest

Not quite, Ralph. A leap century (2000 for example) has, like a leap year,
366 days instead of the regulation 365. The distinction is that the century
years not divisible by 400 (1900, 1800, 1700, for example) are normal
365-day affairs.

Trent C, Nov 5, 2003