Take list of integers n >= 0, move left digit of each term to end of previous term.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =8a(9) =9a(10) =1a(11) =1a(12) =11a(13) =21a(14) =31a(15) =41a(16) =51a(17) =61a(18) =71a(19) =81a(20) =92a(21) =2a(22) =12a(23) =22a(24) =32a(25) =42a(26) =52a(27) =62a(28) =72a(29) =82