Repdigit numbers with repdigit digital sum.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =8a(9) =9a(10) =11a(11) =22a(12) =33a(13) =44a(14) =111a(15) =222a(16) =333a(17) =1111a(18) =2222a(19) =11111a(20) =111111a(21) =1111111a(22) =11111111a(23) =111111111a(24) =11111111111a(25) =22222222222a(26) =33333333333a(27) =44444444444a(28) =55555555555a(29) =66666666666