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 A280248 #7 Sep 08 2022 08:46:18
%S A280248 1,1,3,12,120,2160,45360,2903040,235146240,47029248000,2586608640000,
%T A280248 4469659729920000,348633458933760000,307494710779576320000,
%U A280248 553490479403237376000000,2267097003635660292096000000,308325192494449799725056000000
%N A280248 Partial products of A280246 (Product_{d|n} psi(d)).
%C A280248 psi(n) is the sum of totatives of n (A023896).
%F A280248 a(n) = Product_{i=1..n} A280246(i).
%t A280248 FoldList[#1 #2 &, Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 17}]] (* _Michael De Vlieger_, Dec 30 2016 *)
%o A280248 (Magma) [&*[&*[&+[h: h in [1..d] | GCD(h,d) eq 1]: d in Divisors(k)]: k in [1..n]]: n in [1..100]]
%Y A280248 Cf. A023896, A280246, A280247.
%K A280248 nonn
%O A280248 1,3
%A A280248 _Jaroslav Krizek_, Dec 30 2016