Pitoun's sequence: a(n+1) is digital root of a(0) + ... + a(n).

Terms

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