Friendly numbers (see A074902) such that sigma(n) is not friendly.

Terms

a(0) =66a(1) =210a(2) =282a(3) =364a(4) =510a(5) =642a(6) =930a(7) =966a(8) =1080a(9) =1092a(10) =1146a(11) =1624a(12) =2130a(13) =2226a(14) =2346a(15) =2586a(16) =2676a(17) =3560a(18) =3810a(19) =4278a(20) =4872a(21) =7965