A390005 Perfect squares which are the product of four distinct factorials.

518400, 2073600, 406425600, 3657830400, 2106910310400, 13168189440000, 52672757760000, 210691031040000, 1896219279360000, 229442532802560000, 917770131210240000, 27360196043587190784000000, 246241764392284717056000000, 437763136697395052544000000, 984967057569138868224000000

Offset

1,1

Links

Table of n, a(n) for n=1..15.

Example

Table of n, a(n) for n = 1..11, showing the four factorial factors a!, b!, c!, d! up to d = 12.
.
   n                 a(n)   a!  b!  c!  d!
  ------------------------------------------------------------
   1               518400   1!  3!  5!  6!
   2              2073600   1!  4!  5!  6!
   3            406425600   1!  2!  7!  8!
   4           3657830400   1!  2!  7!  9!
   5        2106910310400   3!  4!  8!  9!
   6       13168189440000   1!  6!  7! 10!  or  3!  5!  7! 10!
   7       52672757760000   4!  5!  7! 10!
   8      210691031040000   2!  6!  8! 10!
   9     1896219279360000   2!  6!  9! 10!
  10   229442532802560000   2!  3! 11! 12!
  11   917770131210240000   2!  4! 11! 12!

Crossrefs

Cf. A387184, A389555, A390003.

Subset of A227652.

Sequence in context: A255034 A256952 A234173 * A226287 A251834 A157803

Adjacent sequences: A390002 A390003 A390004 * A390006 A390007 A390008

Keyword

nonn

Author

Paolo Xausa, Oct 22 2025

Status

approved