login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 60th year, we have over 367,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A069150 Integers of the form k*k!/A062758(k) in the order they appear in A069149, where A062758(k) is the product of squares of divisors of k. 0
1, 2, 24, 720, 4480, 3628800, 1925, 479001600, 387459072, 20922789888000, 6402373705728000, 5516784599040000, 1124000727777607680000, 135277939046250, 24817936069329577574400, 553211880832106496000000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
MATHEMATICA
Rest[Select[Table[k! k/(Times@@Divisors[k])^2, {k, 30}], IntegerQ]] (* Harvey P. Dale, Oct 17 2020 *)
Select[(# * #! / #^DivisorSigma[0, #]) & /@ Range[2, 30], IntegerQ] (* Amiram Eldar, Jul 16 2022 *)
PROG
(PARI) for(n=2, 30, if((n*(n!))%(n^numdiv(n))==0, print1((n*(n!))/(n^numdiv(n)), ", ")))
CROSSREFS
Sequence in context: A030438 A012723 A354335 * A323491 A046977 A309205
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 08 2002
EXTENSIONS
Name clarified by Amiram Eldar, Jul 16 2022
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 9 06:02 EST 2023. Contains 367685 sequences. (Running on oeis4.)