Numbers k such that phi(k + 3) | sigma(k).

Terms

a(0) =3a(1) =6a(2) =7a(3) =11a(4) =15a(5) =19a(6) =21a(7) =23a(8) =27a(9) =31a(10) =33a(11) =42a(12) =43a(13) =51a(14) =57a(15) =59a(16) =62a(17) =69a(18) =70a(19) =71a(20) =77a(21) =79a(22) =83a(23) =84a(24) =87a(25) =93a(26) =103a(27) =131a(28) =139a(29) =141