Position of n-th 1 in A031219.

Terms

a(0) =1a(1) =5a(2) =7a(3) =8a(4) =9a(5) =11a(6) =13a(7) =18a(8) =28a(9) =38a(10) =45a(11) =48a(12) =50a(13) =51a(14) =54a(15) =57a(16) =60a(17) =61a(18) =63a(19) =64a(20) =65a(21) =66a(22) =67a(23) =69a(24) =70a(25) =72a(26) =73a(27) =75a(28) =78a(29) =80