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%I #11 Dec 31 2021 09:56:41
%S 1,2,3,4,20,48,112,864,2916,34560,152064,1728000,9360000,108864000,
%T 1049760000,10668672000,172802851200,2184944025600,32025036718080,
%U 438839318937600,6636767477760000,108637562880000000,1940004332259840000,24494663395141632000,673031429554176000000
%N a(n) = n*Product_{k=1..n} floor(k^((n-k)/(n-k+1))).
%t Table[n*Product[Floor[k^((n-k)/(n-k+1))],{k,n}],{n,30}] (* _Harvey P. Dale_, Sep 13 2020 *)
%o (PARI) a(n) = n*prod(k=2, n-1, floor(k^((n-k)/(n-k+1))));
%K nonn
%O 1,2
%A _Michel Marcus_, Apr 02 2020
%E Definition corrected by _Harvey P. Dale_, Sep 13 2020