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A352170
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Primes p such that p+4, 3*p+4 and 3*p+8 are also prime.
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1
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3, 13, 103, 223, 823, 2953, 7873, 11113, 11863, 13033, 13963, 16063, 22153, 23743, 24763, 27733, 30133, 31513, 34213, 35593, 39883, 41893, 43063, 50383, 51043, 54493, 62983, 65323, 66343, 68473, 71593, 72643, 87793, 88423, 98893, 101203, 106363, 110563, 127873, 134593, 136603, 158563, 164623, 165703
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OFFSET
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1,1
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COMMENTS
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Except for 3, all terms == 13 (mod 30).
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LINKS
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EXAMPLE
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a(4) = 223 is a term because 223, 223+4 = 227, 3*223+4 = 673 and 3*223+8 = 677 are all prime.
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MAPLE
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select(p -> isprime(p) and isprime(p+4) and isprime(3*p+4) and isprime(3*p+8), [3, seq(i, i=13..10^6, 30)]);
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MATHEMATICA
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Select[Range[200000], AllTrue[{#, # + 4, 3*# + 4, 3*# + 8}, PrimeQ] &] (* Amiram Eldar, Mar 07 2022 *)
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PROG
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(Python)
from sympy import sieve, isprime
for p in sieve.primerange(0, 10**6):
if(all(isprime(q) for q in [p+4, 3*p+4, 3*p+8])):
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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