This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A074740 #25 May 04 2025 01:57:52
%S A074740 1,2,6,16,80,240,1680,6720,40320,201600,2217600,8870400,115315200,
%T A074740 807206400,6054048000,38745907200,658680422400,3952082534400,
%U A074740 75089568153600,500597121024000,5256269770752000,57818967478272000,1329836252000256000,7979017512001536000
%N A074740 a(n) = n!*2^(n-1)/Product_{k=1..n} tau(k) where tau = A000005.
%C A074740 Appears to be an integer for n >= 1.
%F A074740 a(n) = A002866(n) / A066843(n). - _Michel Marcus_, Jan 09 2021 [Corrected by _Georg Fischer_, Dec 13 2022]
%t A074740 FoldList[Times, Array[2*#/DivisorSigma[0, #]&, 24]] / 2 (* _Amiram Eldar_, May 04 2025 *)
%o A074740 (PARI) a(n) = n!*2^(n-1)/prod(k=1, n, numdiv(k)); \\ _Michel Marcus_, Jan 09 2021
%Y A074740 Cf. A000005, A002866, A066843.
%K A074740 easy,nonn
%O A074740 1,2
%A A074740 _Benoit Cloitre_, Sep 05 2002