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%I #18 Aug 15 2023 21:04:03
%S 1,0,0,1,4,20,102,630,4480,36288,329890,3326400,36846276,444787200,
%T 5811886080,81729648000,1230752346352,19760412672000,336967037143578,
%U 6082255020441600,115852476579840000,2322315553259520000,48869596859895986086
%N a(n) = floor((n-1)!/n).
%C (h-1)!/h is integer if h belongs to A056653.
%H Vincenzo Librandi, <a href="/A226198/b226198.txt">Table of n, a(n) for n = 1..200</a>
%t Table[Quotient[(n - 1)!, n], {n, 25}]
%o (Magma) [Floor(Factorial(n-1)/n): n in [1..25]];
%Y Cf. A001048 ((n+1)!/n), A056653, A091330 (floor((p-1)!/p), where p is prime), A175787 (prime numbers together with 4).
%K nonn
%O 1,5
%A _Vincenzo Librandi_, May 31 2013
%E Edited by _Bruno Berselli_, May 31 2013