Problems & Puzzles: Puzzles

Puzzle 537. n^n = n mod [prime(n)] Farideh Firoozbakht sent the following puzzle: a) 20201^20201 = 20201  [mod  prime(20201)] b) 20201 is a prime   Can you find more primes with this property (*) ? _____ * See A177005

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J. K. Andersen wrote:

The next prime is 6800832991. There are no others below 10^11

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