Numbers k such that sigma(2k + 2) = 4k.

Terms

a(0) =6a(1) =21a(2) =54a(3) =75a(4) =441a(5) =1071a(6) =4191a(7) =9315a(8) =58311a(9) =4197375a(10) =7685151a(11) =36997695a(12) =268460031a(13) =1073790975a(14) =17180065791