Positions of 2's in Kolakoski sequence (A000002).

Terms

a(0) =2a(1) =3a(2) =6a(3) =8a(4) =9a(5) =11a(6) =12a(7) =15a(8) =18a(9) =19a(10) =21a(11) =24a(12) =26a(13) =27a(14) =30a(15) =33a(16) =35a(17) =36a(18) =38a(19) =39a(20) =42a(21) =44a(22) =45a(23) =47a(24) =50a(25) =53a(26) =54a(27) =56a(28) =57a(29) =60