A023629 a(n) = c([ n/2 ]) + n, with a(1) = 1, c = complement to a.
1, 4, 5, 7, 8, 12, 13, 17, 18, 20, 21, 23, 24, 28, 29, 31, 32, 34, 35, 39, 40, 44, 45, 49, 50, 52, 53, 55, 56, 60, 61, 65, 66, 70, 71, 73, 74, 76, 77, 81, 82, 84, 85, 87, 88, 92, 93, 95, 96, 98, 99, 103, 104, 108, 109, 113, 114, 116, 117, 119, 120, 124, 125, 127
Offset: 1