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Duffinian n.  and  lucky n.

First numbers that belong to both sets:

9, 21, 25, 49, 63, 75, 93, 111, 115, 129, 133, 169, 171, 189, 201, 205, 219, 235, 237, 259, 289, 319, 327, 361, 385, 391, 399, 415, 427, 451, 489, 511, 517, 529, 535, 553, 559, 579, 583, 651, 655, 685, 723, 729, 741, 777, 781, 805, 831, 841, 867, 873, 903, 925, 927, 961, 975, 979, 981, 993, 1011, 1029, 1053, 1057, 1101, 1105, 1147, 1183, 1189, 1197, 1209, 1219, 1251, 1261, 1263, 1281, 1285, 1309, 1357, 1369, 1387, 1389, 1417, 1495, 1497, 1501, 1519, 1533, 1575, 1585, 1587, 1639, 1641, 1645, 1659, 1675, 1705, 1711, 1731, 1737, 1765, 1767, 1771, 1809, 1819, 1839, 1857, 1893, 1899, 1915, 1921, 1963, 1983, 2019, 2023, 2059, 2125, 2127, 2133, 2163, 2173, 2187, 2209, 2215, 2217, 2253, 2257, 2271, 2317, 2323, 2335, 2379, 2407, 2419, 2439, 2461, 2479, 2491, 2493, 2511, 2523, 2527, 2563, 2575, 2587, 2599, 2635, 2649, 2653, 2667, 2763, 2773, 2781, 2785, 2815, 2817, 2827, 2899, 2901, 2923, 2943, 2973, 2977, 2983, 3007, 3027, 3055, 3073, 3091, 3097, 3099, 3133, 3153, 3171, 3175, 3199, 3223, 3235, 3261, 3289, 3297, 3351, 3355, 3403, 3409, 3411, 3427, 3439, 3451, 3477, 3481, 3487, 3565, 3603, 3655, 3661, 3685, 3721, 3747, 3753, 3763, 3781, 3789, 3811, 3843, 3865, 3873, 3891, 3897, 3909, 3951, 3955, 3981, 3991, 3999, 4015, 4033, 4063, 4069, 4081, 4105, 4161, 4165, 4179, 4189, 4237, 4251, 4255, 4269, 4285, 4287, 4315, 4321, 4377, 4383, 4399, 4413, 4431, 4573, 4609, 4629, 4647, 4675, 4699, 4717, 4741, 4761, 4773, 4809, 4819, 4837, 4843, 4863, 4867, 4881, 4887, 4963, 4977, 4989, 5007, 5029, 5041, 5043, 5053, 5103, 5137, 5139, 5149, 5169, 5191, 5211, 5259, 5277, 5293, 5299, 5335, 5341, 5371, 5377, 5409.

Some larger examples :