A227052 - OEIS

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

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 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give

A227052

a(n) = (n^2)! / (n^2-n)! = number of ways of placing n labeled balls into n^2 labeled boxes with at most one ball in each box.

1, 1, 12, 504, 43680, 6375600, 1402410240, 432938943360, 178462987637760, 94670977328928000, 62815650955529472000, 50963773003971232204800, 49633807532904958383820800, 57141374006987657125324185600, 76763145767753986733306290176000, 119005648371962652004288345681920000

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..15.

MATHEMATICA

Table[(n^2)!/(n^2-n)!, {n, 0, 20}] (* Harvey P. Dale, Aug 10 2017 *)

PROG

(Python)

import math

for n in range(20):

print(math.factorial(n*n)//math.factorial(n*n-n), end=', ')