A115802 Sequence A115801 in binary.
0, 1111, 11110, 11111, 111100, 111110, 111111, 1111000, 1111100, 1111110, 1111111, 11110000, 11111000, 11111100, 11111110, 11111111, 111100000, 111110000, 111111000, 111111100, 111111110, 111111111, 1111000000
Offset: 0