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%I #15 Apr 11 2023 04:33:25
%S 1,2,12,96,2880,34560,5806080,92897280,25082265600,2006581248000,
%T 794606174208000,19070548180992000,208250386136432640000,
%U 5831010811820113920000,4198327784510482022400000,3224315738504050193203200000,14799609239733590386802688000000
%N a(n) = Product_{k=1..n} ceiling(n/k)!.
%H G. C. Greubel, <a href="/A308820/b308820.txt">Table of n, a(n) for n = 1..178</a>
%F a(n) = Product_{k=1..n-1} Product_{d|k} (d + 1).
%F a(n) = Product_{k=1..n-1} (k + 1)^floor((n-1)/k). - _Ridouane Oudra_, Apr 10 2023
%p seq(mul(ceil(n/k)!, k=1..n), n=1..30); # _Ridouane Oudra_, Apr 10 2023
%t a[n_] := Product[Ceiling[n/k]!, {k, 1, n}]; Table[a[n], {n, 1, 17}]
%o (PARI) a(n) = prod(k=1, n, ceil(n/k)!); \\ _Michel Marcus_, Jun 27 2019
%o (Magma) [(&*[Factorial(Ceiling(n/(n-j+1))): j in [1..n]]): n in [1..20]]; // _G. C. Greubel_, Mar 08 2023
%o (SageMath)
%o def A308820(n): return product( factorial(ceil(n/(n-k+1))) for k in range(1,n+1))
%o [A308820(n) for n in range(1,21)] # _G. C. Greubel_, Mar 08 2023
%Y Cf. A010786, A020696, A092143, A131385.
%K nonn
%O 1,2
%A _Ilya Gutkovskiy_, Jun 26 2019
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