Odd numbers N for which numerator(sigma(N)/N) is a prime.

Terms

a(0) =9a(1) =25a(2) =289a(3) =729a(4) =1521a(5) =1681a(6) =2401a(7) =3481a(8) =5041a(9) =7921a(10) =10201a(11) =15625a(12) =17161a(13) =27889a(14) =28561a(15) =29929a(16) =83521a(17) =85849a(18) =146689a(19) =257049a(20) =279841a(21) =458329a(22) =491401a(23) =531441a(24) =552049a(25) =579121a(26) =597529a(27) =683929a(28) =703921a(29) =707281