The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ milliseconds is exactly 1 day

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by TekMol on Saturday December 09, 2017 @06:13PM (#15888737)

Units of time are specifically chosen to have 5, 2, and 3 as factors.

Why not 4?

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by jacquesm on Saturday December 09, 2017 @07:15PM (#15888940)

Because you want prime factors.

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by arnarbi on Sunday December 10, 2017 @01:49AM (#15890310)

60 is indeed handy since it divides into 2, 3, 4, 5, and 6. 30 would be much less convenient. Better to drop the 5 (as evidenced by 12 and 24)

I think the gp just generalized a bit to much. Units of time weren't chosen for those (prime) factors. People had simply figured out long time ago that a dozen is a nice round number.

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by tehlike on Saturday December 09, 2017 @06:14PM (#15888742)

4=2^2?

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by greenleafjacob on Saturday December 09, 2017 @06:21PM (#15888763)

I think that is fair as well. 60/4=15 but 30/4 is not a whole number.

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by gerdesj on Saturday December 09, 2017 @06:44PM (#15888842)

No it isn't but a quarter of a half hour is still understandable and is seven and one half minutes which is 7' 30". The ancient Babylonian idea of using 60 (and 360 for angles) is absolute genius.

If you think about it, it is a bit weird but makes so much sense working in base 60. We all do it all of the time.

[ Parent | on HN ]

Re:The fifth hyperfactorial: 5⁵ × 4⁴ × 3³ × 2² × 1¹ millisec... by collinmanderson on Sunday December 10, 2017 @12:04PM (#15892262)

I believe 360 for angles came from 365 days in a year.

[ Parent | on HN ]