Position of n-th 2 in A003137.

Terms

a(0) =2a(1) =8a(2) =9a(3) =11a(4) =13a(5) =14a(6) =23a(7) =32a(8) =34a(9) =37a(10) =40a(11) =41a(12) =42a(13) =45a(14) =48a(15) =50a(16) =51a(17) =54a(18) =57a(19) =59a(20) =60a(21) =61a(22) =63a(23) =64a(24) =66a(25) =67a(26) =68a(27) =80a(28) =92a(29) =95