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 A281025 #22 Nov 02 2017 19:13:10
%S A281025 1,3,6,14,19,163,170,554,716,19916,19927,1264087,1264100,5779940,
%T A281025 7237940,17559860,17559877,75264356677,75264356696,353956196696,
%U A281025 355036399736,1254282070136,1254282070159,16687983940438159,16687983940813159,17351136747929959,17351143890496999
%N A281025 Partial sums of A066570.
%F A281025 a(n) = Sum_{i=1..n} A066570(i).
%p A281025 ListTools:-PartialSums([seq(A066570(n), n=1..27)]); # _Peter Luschny_, Nov 02 2017
%t A281025 Table[Times @@ Select[Range[1, n], !CoprimeQ[#, n]&], {n, 1, 26}] // Accumulate (* _Jean-François Alcover_, Nov 02 2017 *)
%Y A281025 Cf. A066570(n) = the product of cototatives of n.
%K A281025 nonn
%O A281025 1,2
%A A281025 _Jaroslav Krizek_, Jan 14 2017
%E A281025 Edited by _Peter Luschny_, Nov 02 2017