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A277124 Numbers n such that n*prime(n) + n + prime(n) is a prime. 1
1, 2, 3, 5, 6, 8, 9, 11, 13, 14, 20, 21, 26, 29, 30, 33, 35, 36, 39, 41, 43, 49, 54, 55, 62, 68, 69, 75, 76, 79, 81, 89, 90, 105, 110, 113, 117, 119, 126, 134, 141, 146, 154, 162, 174, 176, 178, 179, 186, 191, 195, 207, 209, 215, 216, 222, 225, 227, 230, 231, 234, 237 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

p:= 1: count:= 0: Res:= NULL:

for n from 1 while count < 100 do

  p:= nextprime(p);

  if isprime(n*p+n+p) then

    count:= count+1; Res:= Res, n

  fi

od:

Res; # Robert Israel, Oct 25 2018

PROG

(PARI) is(n) = isprime((n + 1) * (prime(n) + 1) - 1); \\ Altug Alkan, Oct 01 2016

CROSSREFS

Cf. A000040, A086172.

Sequence in context: A186225 A050172 A191877 * A094820 A309793 A093689

Adjacent sequences:  A277121 A277122 A277123 * A277125 A277126 A277127

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Sep 30 2016

STATUS

approved

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Last modified July 28 19:33 EDT 2021. Contains 346335 sequences. (Running on oeis4.)