a(10n+m) is the integer with n+m concatenations of the digit m in base 10, 0<=m<=9.

Terms

a(0) =1a(1) =22a(2) =333a(3) =4444a(4) =55555a(5) =666666a(6) =7777777a(7) =88888888a(8) =999999999a(9) =0a(10) =11a(11) =222a(12) =3333a(13) =44444a(14) =555555a(15) =6666666a(16) =77777777a(17) =888888888a(18) =9999999999a(19) =0a(20) =111a(21) =2222a(22) =33333a(23) =444444a(24) =5555555a(25) =66666666a(26) =777777777a(27) =8888888888a(28) =99999999999a(29) =0