A050877 Numbers n such that 237*2^n-1 is prime.

2, 5, 9, 13, 17, 18, 25, 26, 30, 38, 69, 88, 89, 94, 133, 198, 205, 289, 360, 402, 438, 445, 498, 637, 914, 934, 973, 1265, 2965, 3813, 6096, 11560, 13977, 19816, 33673, 43128, 47869, 50370, 70649, 72809, 82453, 84904, 89210, 102618, 109334, 181610, 421862