This page is under construction.
Soon it will provide more information on the swinging factorial function. But even now you can find the basics in the The On-Line Encyclopedia of Integer Sequences, a fantastic database maintained by N. J. A. Sloane.

n≀ Type All Even Odd
Swinging factorial seq A056040 A000984 A002457
Binomial transform seq A163865 A026375 A163869
- " - , triangle tria A163840 A163841 A163842
- " - , row sums seq A163843 A163844 A163845
Inverse binomial transform seq A163650 A002426 A163872
- " - , triangle tria A163770 A163771 A163772
- " - , row sums seq A163773 A163774 A163775
Scaled form tria A163649 A098473 A163945
Odd part of swinging factorial  seq A163590 A001790 A001803
Radical of n≀  is rad(n≀) seq A163641 A080397 A163640
Primorial(n) / rad(n≀) seq A163644    
Swinging primes seq A163074    
Super swingers seq A163085    
Super duper swingers seq A163086    

Those entries which have a darker background color have been on OEIS before the swinging factorial was introduced. It clearly shows a bias for the even case. Both columns start with family silver type sequences "Formerly M.. N.." (A000984 and A002457).

Divisibility properties of n≀ can be found here.

A000120
σ(n)
A001316
2σ(n)
A049606
2σ(n)−nn!
A001147
(2n−1)≀≀

  

Info box: How to write the swinging factorial.
 
Web designers write ≀ for the symbol ≀. If you use a good browser and have some good free fonts installed you should have no problem to see n≀ perfectly rendered.

\Te\Xni\cans \mi\ght \use \som\eth\ing \like
"\newcommand{\swing}[1]{\ensuremath{{{#1}\wr}}}".

If you are forced to write with some telegraph code use n$.
 
Font designers might think of a sacred erected cobra dancing in front of a snake-charmer. The technical name of the symbol is 'wreath product', the conventional name is Naja.

More information on math fonts and browsers.

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