(1+e)-harmonic numbers: harmonic mean of (1+e)-divisors is an integer.

Terms

a(0) =1a(1) =6a(2) =28a(3) =140a(4) =728a(5) =1638a(6) =2184a(7) =3640a(8) =8008a(9) =8190a(10) =10920a(11) =18620a(12) =23808a(13) =23895a(14) =27846a(15) =37128a(16) =47790a(17) =55860a(18) =69160a(19) =148960a(20) =166656a(21) =189810a(22) =237510a(23) =242060a(24) =316680a(25) =334530a(26) =359600a(27) =406215a(28) =446880a(29) =484120