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 A280982 #11 Sep 08 2022 08:46:18
%S A280982 1,1,2,6,54,486,9720,204120,6531840,241678080,13050616320,
%T A280982 652530816000,50244872832000,4069834699392000,390704131141632000,
%U A280982 41023933769871360000,5538231058932633600000,731046499779107635200000,124277904962448297984000000
%N A280982 Partial products of A024816; a(1) = a(2) = 1.
%F A280982 a(1) = a(2) = 1; for n>2, a(n) = Product_{i=3..n} A024816(i).
%t A280982 FoldList[#1 #2 &, Table[Boole[n <= 2] + n (n + 1)/2 - DivisorSigma[1, n], {n, 19}]] (* _Michael De Vlieger_, Jan 11 2017 *)
%o A280982 (Magma) [1, 1] cat [&*[k*(k+1)/2 - SumOfDivisors(k): k in [3..n]]: n in [3..100]]
%Y A280982 Cf. A024816(n) = sum of nondivisors of n.
%Y A280982 Cf. A076664.
%K A280982 nonn
%O A280982 1,3
%A A280982 _Jaroslav Krizek_, Jan 11 2017