Place where n-th 1 occurs in A023123.

Terms

a(0) =1a(1) =4a(2) =10a(3) =19a(4) =30a(5) =44a(6) =61a(7) =81a(8) =103a(9) =128a(10) =156a(11) =186a(12) =219a(13) =255a(14) =294a(15) =335a(16) =379a(17) =426a(18) =475a(19) =527a(20) =582a(21) =640a(22) =700a(23) =763a(24) =829a(25) =897a(26) =968a(27) =1042a(28) =1119a(29) =1198