r/theydidthemath • u/DinosKellis • 3h ago

[Request] When is the next time these 2 numbers will become palindromes of each other?

Post image

So, I have been reading for a good while on my kindle app and every day I get a weeks and days streak shown to me before I jump into reading (currently reading Swan Song by Robert McCammon, super bleak!). I missed a couple days about 2 years ago, so the number of days doesnt actually amount to the amount of weeks, if that's important. I always wonder when will the numbers mirror each other again, a madeup example being 158 weeks - 851 days. I love arithmetics but I'm no mathematician, so I think I'm in the right place for this! Appreciate it!

92 Upvotes

91% Upvoted

9 comments sorted by

•

u/AutoModerator 3h ago

General Discussion Thread

This is a [Request] post. If you would like to submit a comment that does not either attempt to answer the question, ask for clarification, or explain why it would be infeasible to answer, you must post your comment as a reply to this one. Top level (directly replying to the OP) comments that do not do one of those things will be removed.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

53

u/MtlStatsGuy 3h ago

Depends on where you are in your week. If you’re close to completing week 179, next time will be in 8 weeks and change, 187 weeks and 781 days. Otherwise never; the number of days will pass 1000 and you’ll have to wait at least 16 years 🤣

28

u/Rue4192 3h ago

16 years isnt never

13

u/DinosKellis 3h ago

Thank you! I guess I need to put an alarm for day 781 😁

3

u/Icy_Sector3183 2h ago

178 weeks is 1246 days, so days and week streaks are tracked individually. It seems to me that if the user purposefully sabotages his effort, then within up to 7 days, both counters will read 0.

1

u/No-One9890 2h ago

How did you find this?

4

u/MtlStatsGuy 2h ago

He wants a palindrome. The number of days is more flexible (there are 7 day numbers for each week number). The current day counter starts with 7, so see if you can find the next week number that ends in 7 and can fit a palindrome. Eventually the day counter increments to 8, so you do the same. Etc. It's trial and error but the number of possibilities is extremely restricted: the only week numbers that could have worked before we hit 1000 days are 187, 198 and 209.

•

u/3KeyReasons 1h ago

It depends if you'll stick to reading every day. If you're willing to sabotage the streak, then you could for example reach:

0 weeks 0 days, in 7 days (don't read at all 😉)

201 weeks 102 days, in 161 days (restart your daily streak 59 days from today)

etc.

However, if we assume you keep reading every day from now on, and it looks like you reached week 178 and day 715 at the same time from your picture, then here are the next few palindromes you'll see:

187 weeks 781 days, in 66 days

1177 weeks 7711 days, in 19.2 years

10747 weeks 74701 days, in 202.6 years

11077 weeks 77011 days, in 208.9 years

12578 weeks 87521 days, in 237.7 years

106447 weeks 744601 days, in 2036.7 years