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 A339722 #4 Dec 14 2020 16:01:12
%S A339722 1,-7,-7,21,-7,42,-7,-42,21,42,-7,-105,-7,42,42,84,-7,-105,-7,-105,42,
%T A339722 42,-7,189,21,42,-42,-105,-7,-203,-7,-175,42,42,42,217,-7,42,42,189,
%U A339722 -7,-203,-7,-105,-105,42,-7,-399,21,-105,42,-105,-7,189,42,189,42,42,-7,385
%N A339722 Dirichlet g.f.: Product_{k>=2} 1 / (1 + k^(-s))^7.
%F A339722 a(1) = 1; a(n) = -Sum_{d|n, d < n} A339339(n/d) * a(d).
%F A339722 a(p^k) = A022602(k) for prime p.
%Y A339722 Cf. A022602, A316441, A339339, A339717, A339718, A339719, A339720, A339721.
%K A339722 sign
%O A339722 1,2
%A A339722 _Ilya Gutkovskiy_, Dec 14 2020