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%I #10 Mar 24 2021 15:51:53
%S 557,248137,4085791,519807973
%N Primes p such that p divides (2 + product of primes < p).
%H Norman Luhn, <a href="https://primes.utm.edu/curios/page.php?curio_id=2284">Prime Curios! 557</a>
%e 557 is in the sequence because 2 + A034386(557 - 1) = 557 * 4627335992...5904782776 (220 digits).
%o (Python)
%o from sympy import nextprime
%o def aupto(limit):
%o p, psharp = 3, 2
%o while p <= limit:
%o if (psharp+2)%p == 0: print(p, end=", ")
%o psharp, p = psharp*p, nextprime(p)
%o aupto(500000) # _Michael S. Branicky_, Mar 24 2021
%Y Cf. A338543, A062347, A034386.
%K nonn,hard,more
%O 1,1
%A _Martin Ehrenstein_, Jan 16 2021
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