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A340225 Primes p such that 2*p+q and 2*p+r are prime, where q and r are the next two primes after p. 2
3, 19, 241, 439, 577, 743, 787, 983, 1549, 1637, 1699, 1879, 2273, 2843, 3929, 4157, 4201, 4583, 5669, 5791, 6301, 6659, 7559, 11887, 12163, 12517, 12889, 13007, 13049, 13219, 13759, 13879, 14149, 15139, 18443, 18539, 18959, 19793, 23431, 23629, 23993, 24419, 25127, 26737, 27407, 27739, 27799, 28409 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

a(3) = 241 is a term because it is prime, the next two primes are 251 and 257, and 2*241+251 = 733 and 2*241+257 = 739 are prime.

MAPLE

R:= NULL: count:= 0:

q:= 2: r:= 3:

while count < 100 do

  p:= q; q:= r; r:= nextprime(r);

  if isprime(2*p+q) and isprime(2*p+r) then

    count:= count+1; R:= R, p;

  fi

od:

R;

CROSSREFS

Cf. A340210.

Sequence in context: A230316 A157675 A135754 * A118023 A054590 A261495

Adjacent sequences:  A340222 A340223 A340224 * A340226 A340227 A340228

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Jan 01 2021

STATUS

approved

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Last modified May 25 14:15 EDT 2022. Contains 354071 sequences. (Running on oeis4.)