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 A220849 #47 Nov 02 2021 10:01:55
%S A220849 1,2,3,16,5,432,7,1024,81,2000,11,71663616,13,5488,10125,1048576,17,
%T A220849 816293376,19,2048000000,27783,21296,23,219122084616339456,625,35152,
%U A220849 59049,15420489728,29,2550916800000000000,31,34359738368,107811,78608,214375
%N A220849 a(n) = Product_{d|n} Product_{d_x|n , d_x <= d} d_x.
%C A220849 Conjecture: sequence is injective (all terms of this sequence occur only once).
%C A220849 The subsequence of fixed points consists of 1 together with the primes (A008578). - _Bernard Schott_, Oct 26 2021
%H A220849 Seiichi Manyama, <a href="/A220849/b220849.txt">Table of n, a(n) for n = 1..2000</a> (terms 1..100 from Jaroslav Krizek)
%F A220849 a(p) = p for prime p.
%F A220849 From _Bernard Schott_, Oct 29 2021: (Start)
%F A220849 For p prime and k >= 0, a(p^k) = p^A000292(k).
%F A220849 For n = p*q, p < q primes (A006881), a(n) = p*n^3. (End)
%e A220849 The divisors of 6 are 1, 2, 3, 6. a(n) = 1*(1*2)*(1*2*3)*(1*2*3*6) = 1*2*6*36 = 432.
%t A220849 a[n_] := Module[{d = Divisors[n], nd}, nd = Length[d]; Product[d[[i]]^(nd - i + 1), {i, 1, nd}]]; Array[a, 35] (* _Amiram Eldar_, Oct 23 2021 *)
%o A220849 (PARI) a(n) = my(d=divisors(n)); prod(k=1, #d, vecprod(select(x->(x<=d[k]), d))); \\ _Michel Marcus_, Oct 23 2021
%Y A220849 Cf. A000292, A006881, A007955, A008578 (fixed points), A064945, A266265.
%K A220849 nonn
%O A220849 1,2
%A A220849 _Jaroslav Krizek_, Dec 22 2012
%E A220849 a(24) corrected by _Seiichi Manyama_, Oct 23 2021