Composite numbers k such that sigma(2*k+1)-sigma(k) = k+1.

Terms

a(0) =16a(1) =335a(2) =8399a(3) =12599a(4) =16383a(5) =62999a(6) =546359a(7) =743999a(8) =2815199a(9) =3046655a(10) =3592655a(11) =8422679a(12) =25357439a(13) =26356199a(14) =29318279a(15) =75428999a(16) =112039199a(17) =202417343a(18) =226325999a(19) =329611559a(20) =335894159a(21) =452921039a(22) =589783295a(23) =691547999a(24) =696032399a(25) =772098599a(26) =1189437239a(27) =1512741267