Sum of digits = 8 times number of digits.

Terms

a(0) =8a(1) =79a(2) =88a(3) =97a(4) =699a(5) =789a(6) =798a(7) =879a(8) =888a(9) =897a(10) =969a(11) =978a(12) =987a(13) =996a(14) =5999a(15) =6899a(16) =6989a(17) =6998a(18) =7799a(19) =7889a(20) =7898a(21) =7979a(22) =7988a(23) =7997a(24) =8699a(25) =8789a(26) =8798a(27) =8879a(28) =8888a(29) =8897