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 A173392 #11 May 23 2018 02:44:33
%S A173392 1,1,1,1,2,2,6,12,24,48,720,240,2160,23040,45360,40320,2419200,
%T A173392 1935360,65318400,69672960,163296000,2786918400,754427520000,
%U A173392 22992076800,201180672000,14714929152000,211843247616000,114776447385600,32953394073600000,2410305395097600
%N A173392 Product of nonzero remainders of n mod k, for k = 1,2,3,...,n.
%e A173392 For n = 7; 7 mod k, for k = 1,2,3,...,7: (0,1,1,3,2,1,0). Product of nonzero remainders = 6. a(7) = 6.
%t A173392 Table[Times@@DeleteCases[Mod[n, Range[n]], 0], {n, 30}]
%o A173392 (PARI) a(n) = prod(k=1, n, if (m = n % k, m, 1)); \\ _Michel Marcus_, May 23 2018
%Y A173392 Cf. A004125 (sum of remainders of n mod k).
%K A173392 nonn
%O A173392 1,5
%A A173392 _Jaroslav Krizek_, Nov 22 2010
%E A173392 Extended by _T. D. Noe_, Nov 22 2010