Search a number
pernicious n.  and  Ulam n.

First numbers that belong to both sets:

3, 6, 11, 13, 18, 26, 28, 36, 38, 47, 48, 62, 69, 72, 82, 87, 97, 131, 138, 145, 148, 155, 182, 206, 236, 241, 253, 258, 260, 273, 309, 316, 319, 324, 339, 341, 358, 370, 382, 400, 409, 412, 431, 434, 451, 502, 522, 524, 544, 546, 566, 602, 607, 668, 690, 695, 722, 734, 781, 800, 820, 847, 849, 861, 866, 905, 949, 986, 1025, 1030, 1032, 1081, 1101, 1125, 1208, 1252, 1296, 1308, 1311, 1335, 1377, 1387, 1389, 1404, 1428, 1431, 1462, 1465, 1509, 1514, 1516, 1536, 1538, 1550, 1643, 1646, 1648, 1660, 1682, 1707, 1709, 1721, 1724, 1765, 1770, 1792, 1812, 1858, 1900, 1941, 1946, 2032, 2054, 2056, 2093, 2112, 2134, 2156, 2178, 2249, 2252, 2288, 2330, 2332, 2354, 2371, 2447, 2462, 2486, 2552, 2574, 2581, 2616, 2630, 2633, 2660, 2721, 2748, 2787, 2789, 2816, 2831, 2833, 2899, 2921, 2985, 3041, 3085, 3107, 3109, 3131, 3153, 3205, 3217, 3236, 3239, 3290, 3305, 3368, 3371, 3373, 3393, 3417, 3481, 3525, 3544, 3593, 3608, 3630, 3632, 3649, 3669, 3698, 3723, 3725, 3740, 3762, 3764, 3872, 3916, 3952, 3974, 4040, 4101, 4150, 4153, 4167, 4294, 4297, 4324, 4341, 4363, 4365, 4368, 4390, 4404, 4407, 4470, 4519, 4531, 4534, 4600, 4619, 4622, 4624, 4646, 4729, 4732, 4754, 4756, 4881, 4900, 4903, 4969, 4996, 5018, 5020, 5059, 5096, 5162, 5164, 5181, 5184, 5208, 5272, 5291, 5294, 5296, 5316, 5382, 5484, 5489, 5616, 5665, 5685, 5768, 5795, 5797, 5812, 5829, 5858, 5895, 5902, 5944, 6049, 6112, 6176, 6242, 6244, 6308, 6325, 6352, 6410, 6418, 6420, 6457, 6520, 6550, 6569, 6721, 6806, 6833, 6865, 6872, 6911, 6914, 6916, 6931, 6938, 6982, 7043, 7060, 7192, 7195, 7197, 7219, 7258, 7297, 7300, 7322.

Some larger examples :