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Chen prime  and  oban n.

First numbers that belong to both sets:

3, 5, 7, 11, 13, 17, 19, 23, 29, 37, 53, 59, 67, 83, 89, 307, 311, 317, 337, 353, 359, 379, 389, 503, 509, 557, 563, 569, 577, 587, 599, 617, 653, 659, 677, 683, 719, 769, 787, 797, 809, 811, 827, 829, 839, 857, 863, 877, 887, 911, 919, 937, 953, 977, 983.