Even composite positive integers m such that A052918(m-1)^2 == 1 (mod m).

Terms

a(0) =4a(1) =8a(2) =16a(3) =32a(4) =68a(5) =248a(6) =268a(7) =544a(8) =1328a(9) =4216a(10) =4768a(11) =9112a(12) =9376a(13) =12664a(14) =20128a(15) =22112a(16) =24536a(17) =25544a(18) =30488a(19) =43262a(20) =61574a(21) =125792a(22) =148004a(23) =304792a(24) =398248a(25) =493646a(26) =648848a(27) =913456a(28) =1036664a(29) =1975784