Numbers k such that sigma(k) divides k*phi(k).

Terms

a(0) =1a(1) =6a(2) =15a(3) =28a(4) =84a(5) =95a(6) =140a(7) =182a(8) =190a(9) =248a(10) =270a(11) =287a(12) =308a(13) =357a(14) =420a(15) =455a(16) =477a(17) =496a(18) =570a(19) =672a(20) =744a(21) =819a(22) =840a(23) =910a(24) =1199a(25) =1428a(26) =1488a(27) =1547a(28) =1638a(29) =1722