a(n) is the smallest number m such that the sum of the digits of n+m is n.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =9a(10) =18a(11) =27a(12) =36a(13) =45a(14) =54a(15) =63a(16) =72a(17) =81a(18) =180a(19) =279a(20) =378a(21) =477a(22) =576a(23) =675a(24) =774a(25) =873a(26) =972a(27) =1971a(28) =2970a(29) =3969