41
41 = 2 + 3 + 5 + 7 + 11 + 13
241 - 1 = 13367 * 164511353
n2 + n + 41 gives prime values for n = 0 to 39
1041 - 1 = 3 * 3 * 83 * 1231 * 538987 * 201763709900322803748657942361
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