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 A140197 #6 Sep 12 2019 11:55:14 %S A140197 55,301,3631,6085,19495,70645,147853,438205,605695,669781,888823, %T A140197 1694695,3060301,3640783,6692791,7998895,9857245,12912535,15443365, %U A140197 17109895,17690941,22819693,28048231,34936663,58178245,75203725,95263573,124984543,127160245,155267965 %N A140197 A137576((k-1)/2) for composite numbers k from A141229. %t A140197 r[n_] := EulerPhi[n]/MultiplicativeOrder[2, n]; d[n_] := DivisorSum[n, r[#] &]; f[n_] := (m = MultiplicativeOrder[2, n])*d[n] - m + 1; f /@ Select[Range[10^5], CompositeQ[#] && Total@(r /@ Divisors[#]) - 1 == 3 &] (* _Amiram Eldar_, Sep 12 2019 *) %Y A140197 Cf. A137576, A141229, A006694, A002326. %K A140197 nonn %O A140197 1,1 %A A140197 _Vladimir Shevelev_, Jun 15 2008 %E A140197 More terms from _Amiram Eldar_, Sep 12 2019