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 A277174 #16 Oct 06 2016 02:44:35
%S A277174 1,1,4,36,288,7200,259200,12700800,203212800,5486745600,548674560000,
%T A277174 66389621760000,4780052766720000,807828917575680000,
%U A277174 158334467844833280000,35625255265087488000000,1140008168482799616000000,329462360691529089024000000
%N A277174 a(n) = Product_{i=1..n} i*rad(i) where rad(n) = A007947(n).
%H A277174 Robert Israel, <a href="/A277174/b277174.txt">Table of n, a(n) for n = 0..268</a>
%F A277174 a(n) = n! * A048803(n). - _Robert Israel_, Oct 02 2016
%p A277174 A277174 := proc(n) local rad, i;
%p A277174 rad := n -> mul(k, k in numtheory:-factorset(n));
%p A277174 mul(i * rad(i), i=1..n) end:
%p A277174 seq(A277174(i), i=0..17);
%t A277174 Table[Product[i Last@ Select[Divisors@ i, SquareFreeQ], {i, n}], {n, 0, 17}] (* _Michael De Vlieger_, Oct 02 2016 *)
%o A277174 (PARI) a(n) = prod(i=1, n, i*factorback(factorint(i)[, 1])); \\ _Michel Marcus_, Oct 03 2016
%Y A277174 Cf. A007947, A048803.
%K A277174 nonn
%O A277174 0,3
%A A277174 _Peter Luschny_, Oct 02 2016