Successive decimal digits of triangular numbers.

Terms

a(0) =0a(1) =1a(2) =3a(3) =6a(4) =1a(5) =0a(6) =1a(7) =5a(8) =2a(9) =1a(10) =2a(11) =8a(12) =3a(13) =6a(14) =4a(15) =5a(16) =5a(17) =5a(18) =6a(19) =6a(20) =7a(21) =8a(22) =9a(23) =1a(24) =1a(25) =0a(26) =5a(27) =1a(28) =2a(29) =0