Position of n-th 1 in A031018.

Terms

a(0) =1a(1) =4a(2) =6a(3) =8a(4) =10a(5) =13a(6) =27a(7) =41a(8) =46a(9) =49a(10) =52a(11) =55a(12) =58a(13) =59a(14) =60a(15) =61a(16) =62a(17) =64a(18) =65a(19) =67a(20) =70a(21) =73a(22) =76a(23) =79a(24) =81a(25) =82a(26) =85a(27) =88a(28) =91a(29) =94