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aban n.  and  centered triangular n.

First numbers that belong to both sets:

1, 4, 10, 19, 31, 46, 64, 85, 109, 136, 166, 199, 235, 274, 316, 361, 409, 460, 514, 571, 631, 694, 760, 829, 901, 976, 1000009, 8000686, 9000076, 12000619, 20000179, 25000210, 28000081, 35000596, 49000411, 81000679, 109000651, 110000299, 113000581, 122000014, 130000186, 147000151, 184000051, 194000635, 252000724, 264000034, 305000011, 366000031, 377000194, 379000381, 437000539, 538000174, 595000459, 670000636, 723000106, 827000821, 868000621, 874000774, 984000235, 1098000121, 1188000460, 1215000091, 1311000799, 1374000736, 1381000960, 1428000256, 1515000271, 1621000504, 1656000454, 1713000964, 1830000169, 1885000576, 1963000201, 2053000531, 2062000279, 2188000585, 2376000301, 2414000359, 2454000385, 2498000509, 2745000094, 2805000439, 3050000335, 3063000799, 3294000274, 3394000585, 3409000885, 3630000664, 3686000419, 3895000210, 3953000341, 4031000641, 4090000960, 4233000010, 4344000616, 4415000635, 4437000235, 4567000294, 4659000139, 5114000566, 5521000339, 5556000691, 5736000124, 5978000656, 6034000801, 6083000164, 6507000949, 6600000835, 6766000624, 6859000894, 7111000135, 7300000324, 7424000329, 7454000314, 7625000260, 7739000119, 7825000954, 8247000079, 8353000129, 8582000941, 8770000249, 9150000760, 9289000414, 9597000235, 9603000235, 10127000584, 10375000084, 10650000574, 10728000496, 10935000814, 11106000244, 11585000710, 12019000024, 12069000451, 12516000556, 12589000399, 13213000756, 13633000336, 13698000424, 14204000116, 14542000474, 14555000296, 14945000509, 15213000835, 16207000456, 16459000876, 16662000946, 16731000235, 17587000021, 18481000504, 18556000429, 19390000081, 19433000794, 20227000879, 21006000874, 21134000854, 21994000516, 22603000906, 23027000851, 23088000241, 23609000089, 24236000149, 24315000664, 24605000551, 24705000841, 25508000431, 25770000385, 26444000101, 26582000644, 27090000235, 28033000714, 28681000510, 28806000994, 29491000309, 29673000829, 29992000510, 30006000991, 34505000839, 34779000946, 35218000135, 35339000386, 36101000449, 36392000041, 36748000381, 37002000991, 37316000026, 37979000281, 38097000085, 38208000601, 38394000235, 38406000235, 38479000591, 38777000809, 39323000749, 41182000996, 42154000024, 43622000335, 44005000681, 44319000316, 46168000924, 46672000264, 47108000161, 47662000156, 47708000911, 49195000054, 49754000251, 50887000174, 51028000384, 51203000710, 51678000235, 52191000739, 52442000131, 52652000944, 53202000856, 53689000366, 55754000464, 55846000885, 55879000636, 56516000014, 56678000761, 56748000781, 58438000531, 58836000826, 59654000260, 59845000234, 60347000260, 60515000389, 61236000676, 61893000046, 62727000796, 63305000686, 64303000885, 64708000354, 66716000569, 67152000961, 67286000731, 68096000134, 68943000235, 69494000710, 71119000921, 71501000869, 72070000831, 72247000141, 74223000706, 74422000189, 74794000051, 75563000371, 76533000421, 76594000306, 77021000101, 78329000611, 78983000335, 79850000179, 79913000116, 80354000926, 80511000979, 80799000286, 81741000241, 81933000124, 82272000919, 82324000756, 82395000019, 82711000831, 82742000041, 83458000144, 84562000384, 85205000836, 85313000566, 86196000559, 86391000235, 86409000235, 86856000085, 87562000909, 87903000244, 90007000084, 90118000486, 90419000764, 90559000459, 91345000135, 93375000751.

Some larger examples :