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 A074319 #7 Jul 11 2015 05:47:52
%S A074319 2,144,2073600,17557585920000,192668014586363904000000,
%T A074319 5116462645455544976110780416000000000,
%U A074319 551096864092633744724294766310605805584384000000000000
%N A074319 Product of next n factorials.
%C A074319 Product of next n factorials gives this sequence, while product of first n factorials = superfactorial is A000178. If superfactorial is sf(n) then this function, "uppersuperfactorial", is usf(n)= sf(2n)/sf(n).
%F A074319 product(i!, i=n+1, 2n).
%F A074319 a(n) ~ 2^(2*n^2 + 5*n/2 + 5/12) * n^(n*(3*n/2+1)) * Pi^(n/2) / exp(n*(9*n+4)/4). - _Vaclav Kotesovec_, Jul 11 2015
%t A074319 Table[Product[i!, {i, n+1, 2n}], {n, 10}]
%Y A074319 Cf. A000178.
%K A074319 nonn
%O A074319 1,1
%A A074319 _Zak Seidov_, Sep 22 2002