Odd composite numbers k such that cototient(k) - phi(k) = k - 2*phi(k) is an odd prime.

Terms

a(0) =165a(1) =195a(2) =5187a(3) =5865a(4) =7395a(5) =10005a(6) =15045a(7) =16215a(8) =21165a(9) =22695a(10) =27285a(11) =37995a(12) =42585a(13) =44115a(14) =50235a(15) =57885a(16) =59415a(17) =60945a(18) =64005a(19) =310845a(20) =346035a(21) =347565a(22) =486795a(23) =635205a(24) =707115a(25) =890445a(26) =979455a(27) =994755a(28) =1049835a(29) =1070535