A026067 a(n) = (d(n)-r(n))/2, where d = A026066 and r is the periodic sequence with fundamental period (1,0,0,0).

52, 84, 123, 170, 225, 290, 364, 448, 542, 648, 765, 894, 1035, 1190, 1358, 1540, 1736, 1948, 2175, 2418, 2677, 2954, 3248, 3560, 3890, 4240, 4609, 4998, 5407, 5838, 6290, 6764, 7260, 7780, 8323, 8890, 9481, 10098, 10740, 11408, 12102, 12824, 13573, 14350, 15155, 15990, 16854