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A340712 Primes p such that p divides (2 + product of primes < p). 0
557, 248137, 4085791, 519807973 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

Norman Luhn, Prime Curios! 557

EXAMPLE

557 is in the sequence because 2 + A034386(557 - 1) = 557 * 4627335992...5904782776 (220 digits).

PROG

(Python)

from sympy import nextprime

def aupto(limit):

  p, psharp = 3, 2

  while p <= limit:

    if (psharp+2)%p == 0: print(p, end=", ")

    psharp, p = psharp*p, nextprime(p)

aupto(500000) # Michael S. Branicky, Mar 24 2021

CROSSREFS

Cf. A338543, A062347, A034386.

Sequence in context: A105979 A183779 A342825 * A071393 A253290 A206123

Adjacent sequences:  A340709 A340710 A340711 * A340713 A340714 A340715

KEYWORD

nonn,hard,more

AUTHOR

Martin Ehrenstein, Jan 16 2021

STATUS

approved

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Last modified October 17 12:35 EDT 2021. Contains 348048 sequences. (Running on oeis4.)