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evil n.  and  triangular n.

First numbers that belong to both sets:

3, 6, 10, 15, 36, 45, 66, 78, 105, 120, 136, 153, 190, 210, 231, 300, 325, 378, 435, 528, 561, 630, 703, 741, 780, 903, 946, 990, 1035, 1128, 1176, 1275, 1326, 1596, 1711, 1830, 1953, 2016, 2080, 2145, 2278, 2415, 2556, 2628, 2701, 2775, 2926, 3081, 3321, 3486, 3570, 3741, 3828, 4005, 4095, 4278, 4465, 4656, 4851, 5050, 5460, 5778, 5886, 6216, 6328, 6441, 6555, 6670, 6903, 7140, 7381, 7626, 7875, 8256, 8385, 8646, 8911, 9180, 9453, 9730, 10011, 10153, 11026, 11325, 11628, 11781, 11935, 12246, 12720, 13041, 13203, 13530, 14028, 14535, 14706, 14878, 15225, 15400, 15576, 15753, 15931, 16471, 17391, 17578, 17955, 18336, 18528, 18915, 19306, 19503, 20100, 20503, 20706, 20910, 22155, 22366, 22578, 23005, 23220, 23436, 23653, 24090, 24753, 25200, 26106, 27261, 27495, 27966, 28680, 28920, 29403, 29646, 30381, 30876, 31375, 31878, 32385, 32640, 32896, 33153, 33670, 34191, 34716, 35245, 36046, 36315, 36856, 37128, 37401, 37675, 37950, 39060, 39340, 39621, 39903, 40186, 40470, 40755, 41328, 41905, 42195, 42486, 42778, 43365, 44253, 44551, 45150, 45451, 46665, 46971, 47895, 48516, 49455, 50086, 50403, 50721, 51681, 52003, 52326, 52975, 54615, 54946, 55278, 55611, 55945, 56280, 56616, 57291, 57630, 57970, 58311, 59340, 59685, 60031, 60726, 61075, 61425, 62128, 63903, 64620, 65703, 66066, 66795, 67896, 69006, 69378, 69751, 70876, 71253, 72390, 73153, 73920, 74691, 75466, 75855, 77028, 77421, 78210, 78606, 79401, 79800, 80601, 81003, 81810, 83028, 83845, 85078, 86320, 87153, 87571, 90100, 91806, 92235, 94395, 94830, 95703, 96580, 97020, 98790, 99235, 100128, 100576, 101475, 101926, 102831, 103285, 105111, 105570, 106030, 106491, 106953, 107416, 107880, 108345, 108811, 110215, 111156, 112575, 113050, 113526, 115440, 115921, 116403, 116886, 117370, 120295, 121278, 121771, 122760, 123753, 125250, 125751, 126756, 127765, 128778, 129795, 131328, 131841, 132870, 133903.

Some larger examples :