Composite and even n such that phi(n) * sigma(n) is one less than a square.

Terms

a(0) =6a(1) =22a(2) =44a(3) =76a(4) =82a(5) =140a(6) =190a(7) =354a(8) =392a(9) =650a(10) =944a(11) =1072a(12) =1142a(13) =1150a(14) =1668a(15) =2276a(16) =4176a(17) =4192a(18) =4262a(19) =5090a(20) =7260a(21) =8660a(22) =15026a(23) =16064a(24) =22926a(25) =29746a(26) =39436a(27) =42872a(28) =74666a(29) =87498