Search a number
practical n.  and  tau n.

First numbers that belong to both sets:

1, 2, 8, 12, 18, 24, 36, 40, 56, 60, 72, 80, 84, 88, 96, 104, 108, 128, 132, 156, 180, 204, 228, 240, 252, 276, 288, 348, 360, 384, 396, 448, 450, 468, 480, 504, 560, 600, 612, 640, 672, 684, 720, 792, 828, 864, 880, 882, 896, 936, 972, 1040, 1044, 1056, 1116, 1152, 1176, 1200, 1224, 1248, 1260, 1332, 1344, 1360, 1368, 1408, 1440, 1476, 1520, 1548, 1620, 1632, 1656, 1664, 1680, 1692, 1800, 1824, 1840, 1908, 1920, 1944, 1980, 2000, 2016, 2088, 2124, 2160, 2176, 2178, 2196, 2208, 2232, 2240, 2320, 2340, 2412, 2432, 2480, 2556, 2560, 2628, 2640, 2664, 2688, 2700, 2772, 2784, 2844, 2904, 2944, 2952, 2960, 2976, 2988, 3042, 3060, 3096, 3120, 3168, 3204, 3240, 3276, 3280, 3360, 3384, 3420, 3440, 3456, 3528, 3552, 3600, 3712, 3744, 3760, 3816, 3936, 3968, 4032, 4050, 4056, 4080, 4128, 4140, 4224, 4240, 4248, 4284, 4320, 4392, 4480, 4500, 4512, 4560, 4720, 4736, 4788, 4824, 4860, 4880, 4896, 4928, 4992, 5000, 5040, 5088, 5112, 5148, 5202, 5220, 5248, 5256, 5280, 5292, 5360, 5472, 5504, 5520, 5580, 5664, 5680, 5688, 5760, 5796, 5824, 5840, 5856, 5976, 6000, 6016, 6048, 6144, 6160, 6240, 6320, 6408, 6432, 6498, 6528, 6624, 6640, 6660, 6720, 6732, 6784, 6804, 6816, 6912, 6936, 6960, 6984, 7008, 7040, 7120, 7272, 7280, 7296, 7308, 7380, 7392, 7416, 7440, 7500, 7524, 7552, 7584, 7616, 7680, 7704, 7740, 7760, 7776, 7808, 7812, 7848, 7920, 7956, 7968, 8064, 8080, 8100, 8136, 8160, 8240, 8320, 8352, 8400, 8460, 8512, 8544, 8560, 8576, 8664, 8712, 8720, 8736, 8832, 8880, 8892, 8928, 9040, 9088, 9108, 9120, 9144, 9312, 9324, 9344, 9360, 9408, 9432, 9504, 9520, 9522, 9540, 9600, 9696, 9840, 9856, 9864.

Some larger examples :