Numbers k such that squarefree part of sigma(k) is equal to squarefree part of 2*k.

Terms

a(0) =6a(1) =28a(2) =468a(3) =496a(4) =775a(5) =2268a(6) =3780a(7) =4655a(8) =7448a(9) =8128a(10) =9000a(11) =10880a(12) =10976a(13) =25137a(14) =40131a(15) =40176a(16) =58752a(17) =62775a(18) =66960a(19) =91000a(20) =137541a(21) =137940a(22) =140800a(23) =160930a(24) =167400a(25) =173600a(26) =195938a(27) =224450a(28) =307125a(29) =377055