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junction n.  and  unprimeable n.

First numbers that belong to both sets:

204, 206, 208, 515, 620, 622, 1415, 1506, 1508, 1710, 1712, 1714, 1716, 1718, 1920, 1922, 1924, 1926, 2105, 2406, 2408, 2515, 2820, 2822, 2824, 2826, 3508, 3815, 4105, 4315, 4410, 4412, 4414, 4416, 4418, 4610, 4612, 4614, 4616, 4618, 4715, 4820, 4822, 4824, 4826, 4828, 4925, 5120, 5122, 5215, 5310, 5312, 5314, 5316, 5318, 5425, 5615, 5720, 5722, 5724, 5726, 5728, 5914, 5916, 5918, 6410, 6412, 6414, 6416, 6418, 6515, 6620, 6622, 6624, 6626, 6628, 6725, 6814, 6816, 6818, 6925, 7110, 7112, 7114, 7116, 7118, 7310, 7312, 7314, 7316, 7318, 7425, 7615, 7730, 8020, 8022, 8025, 8614, 8616, 8618, 8630, 8725, 9030, 9032, 9034, 9110, 9112, 9114, 9116, 9118, 9215, 9918, 10012, 10014, 10016, 10018, 10020, 10022, 10024, 10025, 10205, 10405, 10415, 10815, 10825, 10910, 10912, 10914, 10916, 10918, 10920, 10922, 10924, 10926, 11010, 11012, 11014, 11015, 11016, 11105, 11204, 11206, 11208, 11220, 11305, 11406, 11408, 11608, 11725, 11915, 12020, 12022, 12024, 12026, 12028, 12120, 12310, 12312, 12314, 12316, 12318, 12625, 12815, 13010, 13012, 13014, 13015, 13016, 13018, 13025, 13115, 13206, 13208, 13408, 13812, 13814, 13816, 13818, 14110, 14112, 14114, 14116, 14118, 14120, 14122, 14215, 14310, 14312, 14314, 14316, 14318, 14520, 14522, 14524, 14526, 14615, 14914, 14916, 14918, 15006, 15008, 15020, 15025, 15115, 15208, 15715, 15830, 16015, 16018, 16020, 16022, 16024, 16026, 16028, 16320, 16322, 16324, 16326, 16625, 16714, 16716, 16718, 16730, 16916, 16918, 17008, 17210, 17212, 17214, 17216, 17218, 17220, 17222, 17224, 17226, 17420, 17422, 17424, 17426, 17428, 17525, 17614, 17616, 17618, 17630, 17816, 17818, 18020, 18022, 18024, 18026, 18028, 18030, 18032, 18034, 18625, 18720, 18722, 18724, 18726, 18728, 18825, 18920, 18922, 18924, 18926, 18928, 18930, 18932, 18934, 19020, 19022, 19024, 19025, 19115, 19220, 19222, 19224, 19226, 19228.

Some larger examples :