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centered pentagonal n.  and  unprimeable n.

First numbers that belong to both sets:

1266, 2326, 4306, 7426, 8556, 9456, 13506, 18276, 22326, 29976, 44556, 45226, 52926, 66016, 69306, 78766, 90726, 102516, 105576, 106606, 118266, 123766, 132826, 141016, 142206, 150676, 156876, 165766, 172266, 181576, 188376, 192516, 193906, 199516, 209526, 210976, 222756, 228766, 239476, 245706, 266506, 279726, 284766, 363856, 365766, 371526, 389076, 395016, 397006, 413106, 419226, 437856, 471976, 478516, 489516, 496176, 514156, 525556, 534766, 544056, 551076, 553426, 572406, 579606, 601476, 618766, 631266, 638826, 641356, 651526, 659206, 669516, 693006, 700926, 703576, 711556, 722266, 724956, 733056, 735766, 757626, 779806, 802306, 810826, 825126, 833766, 859956, 904506, 919606, 928726, 931776, 978126, 981256, 1032016, 1044906, 1107226, 1110556, 1123926, 1134006, 1137376, 1174776, 1202356, 1205826, 1216266, 1230256, 1244326, 1247856, 1262026, 1272706, 1287016, 1301406, 1363456, 1378266, 1389426, 1423176, 1434516, 1449706, 1515156, 1526856, 1530766, 1562226, 1594006, 1638226, 1654456, 1658526, 1674856, 1736806, 1757706, 1770306, 1838266, 1859766, 1894426, 1911876, 1942606, 1947016, 1964706, 2031756, 2054356, 2086206, 2104516, 2122906, 2127516, 2141376, 2197266, 2220766, 2277676, 2292016, 2311206, 2354676, 2408356, 2432956, 2507506, 2547726, 2567956, 2593356, 2608656, 2654826, 2717016, 2737906, 2753626, 2774656, 2779926, 2795766, 2801056, 2838226, 2859576, 2864926, 2924106, 2967526, 2989356, 3038766, 3105276, 3150016, 3212056, 3257556, 3263266, 3286156, 3326406, 3332176, 3355306, 3378516, 3395976, 3425176, 3448626, 3466266, 3489856, 3495766, 3561106, 3567076, 3591006, 3615016, 3687526, 3754626, 3779176, 3803806, 3828516, 3909376, 4010056, 4029076, 4035426, 4054506, 4080016, 4112016, 4131276, 4157026, 4189326, 4234756, 4267356, 4286976, 4293526, 4313206, 4346106, 4365906, 4392376, 4418926, 4478956, 4505766, 4525926, 4586676, 4668306, 4688826, 4695676, 4723126, 4771356, 4778266, 4882516, 4938576, 4973776, 4994956, 5002026, 5087256, 5108676, 5173206, 5202016, 5230906, 5259876, 5339956, 5347266, 5369226, 5428006, 5457516, 5487106, 5516776, 5524206, 5546526, 5613756, 5666326, 5704026, 5726706, 5757016, 5817876, 5848426, 5879056, 6010126, 6041176, 6095706, 6158326, 6166176, 6189756, 6197626, 6380016, 6388006, 6412006, 6420016, 6484276, 6508456, 6540766, 6548856, 6573156, 6581266, 6605626, 6646326, 6736306, 6777406, 6835156, 6868266, 6876556, 6943056, 6968076, 7009876.

Some larger examples :