Numbers for which the harmonic mean of nontrivial divisors is an integer.

Terms

a(0) =4a(1) =9a(2) =25a(3) =49a(4) =121a(5) =169a(6) =289a(7) =345a(8) =361a(9) =529a(10) =841a(11) =961a(12) =1050a(13) =1369a(14) =1645a(15) =1681a(16) =1849a(17) =2209a(18) =2809a(19) =3481a(20) =3721a(21) =4386a(22) =4489a(23) =5041a(24) =5329a(25) =6241a(26) =6489a(27) =6889a(28) =7921a(29) =8041