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September 14

Fibonacci numbers and Friday the 13th

Yesterday was a Friday the 13th. But there is also an interesting coincidence with Fibonacci numbers that will occur in 2021. Namely, August 13, 2021, which happens to be a Friday the 13th, could also be written (in the United States) as 8/13/21, which consists of three consecutive Fibonacci numbers.

Does anyone think that we will have a Fibonacci numbers celebration on August 13, 2021 (e.g. a cake with the Fibonacci sequence on it)?

In the Julian calendar, August 13 was on a Friday in AD 521, 1221, and (in Greece) 1921. In the Gregorian calendar, August 13 was on a Friday in 1621. Of course, because the Gregorian calendar repeats every four centuries, August 13 will also be on a Friday in 2421 and 2821. GeoffreyT2000 (talk) 14:48, 14 September 2019 (UTC)[reply]

We could call it phi-day the 13th :) Much of the world would write it as 13/8/21, not quite as compelling, but already there's 3/14 as pi day and even 6/28 as tau day. --RDBury (talk) 17:46, 14 September 2019 (UTC)[reply]

November 23 is Fibonacci Day. An article was deleted as an alleged hoax. I'm not sure it's worth an article but "Fibonacci day" "November 23" finds many sources. I guess 01:12:35 on 8/13/21 will get some attention at the time. PrimeHunter (talk)

You forgot that Friday, as the 5th day of week is also part of the Fibonacci sequence ;) 93.136.115.136 (talk) 08:17, 15 September 2019 (UTC)[reply]

Maybe we need an American Wikipedia just for people who write dates illogically. It took too much of my brain power to keep translating that strange notation used by only 5% of the world's population. Will the US keep that silliness up forever? HiLo48 (talk) 02:29, 15 September 2019 (UTC)[reply]

Please avoid arguing personal prejudices here. "8/13/21" is a perfectly logical way to abbreviate "August 13, '21" since it keeps the components in the same order. Other notations such as the international standard 2021-08-13 are logical for other reasons. --76.69.116.4 (talk) 05:56, 15 September 2019 (UTC)[reply]

My personal preference is for simplicity and logic. Neither of the American usages you illustrated display those characteristics. HiLo48 (talk) 07:02, 15 September 2019 (UTC)[reply]

(1) If you push the argument that the US usage is absurd because the items are not ordered, you will find that 2021-08-13 12:34 is more logical than 13-08-2021 12:34. (I do think the US usage is absurd, but the dd-mm-yyyy is only slightly less so.) (2) Decimal time is simple and logic. I doubt you use it. Tigraan^{Click here to contact me} 09:21, 19 September 2019 (UTC)[reply]

The original query is asking for a prediction and I'm afraid that is also off-topic here. --76.69.116.4 (talk) 05:56, 15 September 2019 (UTC)[reply]

Couldn't some genius work out the probability of such an event occurring? -- Jack of Oz ^{[pleasantries]} 23:48, 18 September 2019 (UTC)[reply]

Will we have a celebration, with cake? Well yes, if @GeoffreyT2000: chooses to organise it. {The poster formerly known as 87.81.230.195} 90.202.210.107 (talk) 12:23, 19 September 2019 (UTC)[reply]