Numbers n such that sigma(n) and d(n) are both harmonic (Ore) numbers.

Terms

a(0) =1a(1) =12a(2) =76a(3) =932a(4) =4975a(5) =10636a(6) =14975a(7) =16819a(8) =18716a(9) =19269a(10) =46144a(11) =50699a(12) =99196a(13) =134975a(14) =164421a(15) =205916a(16) =359232a(17) =457792a(18) =462272a(19) =468032a(20) =622436a(21) =624211a(22) =812156a(23) =879836a(24) =1308716a(25) =1700991a(26) =1872731a(27) =2096192a(28) =2195776a(29) =2275136