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repunit  and  semiprime

First numbers that belong to both sets:

15, 21, 57, 85, 91, 111, 121, 133, 183, 259, 341, 381, 511, 553, 703, 781, 813, 871, 993, 1057, 1111, 1191, 1261, 1333, 1555, 1561, 1641, 1807, 1893, 1981, 2047, 2071, 2257, 2353, 2653, 2757, 2863, 3193, 3661, 4033, 4291, 4369, 4681, 4971, 5257, 5403, 5461, 5853, 6807, 6973, 7141, 7311, 7483, 8373, 8557, 8743, 9121, 9313, 9507, 9703, 9841, 10713, 10921, 11111, 11773, 12657, 12883, 13111, 13341, 14521, 15007, 15253, 15501, 15751, 16003, 16105, 16257, 16771, 17557, 18091, 18633, 19741, 21171, 22053, 23257, 24493, 24807, 27723, 29071, 29413, 30451, 30801, 32221, 32581, 33307, 33673, 34411, 34783, 35157, 36291, 38221, 39007, 39801, 40201, 40603, 41007, 41371, 41821, 43057, 44311, 45157, 45583, 46873, 47989, 48181, 49507, 49953, 50401, 50851, 51757, 52213, 54241, 54523, 54991, 56407, 57361, 57841, 58323, 59293, 59781, 61753, 62251, 63253, 63757, 65281, 65641, 66307, 66823, 67341, 67861, 68383, 69961, 70491, 71557, 73171, 73713, 75351, 76453, 78681, 79243, 81511, 82083, 86731, 88507, 88573, 89701, 90301, 91507, 92113, 93943, 95173, 97033, 100173, 100807, 101443, 102721, 103363, 104653, 105951, 107257, 109231, 111151, 111223, 112561, 114583, 115261, 116623, 119371, 122851, 124963, 127093, 128523, 131407, 132133, 133591, 137257, 137271, 137561, 138013, 140251, 141001, 141753, 142507, 147841, 148611, 149383, 150933, 151711, 152491, 159601, 161203, 166057, 167691, 169333, 170983, 175981, 176821, 177663, 182757, 183613, 187057, 191407, 194041, 194923, 195807, 196693, 197581, 199363, 202051, 204205, 204757, 212061, 212983, 213907, 216691, 218557, 219493, 220431, 223257, 224203, 225151, 226101, 228007, 229921, 230881, 232807, 233773, 236683, 238633, 241573, 242557, 243543, 246513, 248503, 253513, 254521, 257557, 259591, 260611, 261633, 264711, 265741, 266773, 267807, 269881, 275101, 277203, 279313, 285691, 289983, 291061, 291919, 294307, 297571, 298663, 300853, 301951, 306363, 309693, 311923, 313041, 315283, 317533, 318661, 325471, 328903, 330051, 334663, 336981, 342811.

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