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Numbers k such that the three numbers k+3, k-3 and k+5 are all prime.
2

%I #18 Apr 14 2022 05:32:32

%S 8,14,26,56,104,134,176,194,236,266,566,596,656,824,1016,1226,1286,

%T 1484,1604,1616,1874,2084,2336,2546,2966,3254,3326,3464,3536,3764,

%U 3914,3926,4016,4214,4256,4646,4796,5006,5276,5474,5654,5846,5864,6266,6356,6566

%N Numbers k such that the three numbers k+3, k-3 and k+5 are all prime.

%C Subset of A087695. - _R. J. Mathar_, Sep 24 2008

%H Amiram Eldar, <a href="/A144842/b144842.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeTriplet.html">Prime Triplet</a>.

%F a(n) = A046138(n) + 3. - _R. J. Mathar_, Sep 24 2008

%t Select[Range[7000], And @@ PrimeQ[# + {-3, 3, 5}] &] (* _Amiram Eldar_, Apr 14 2022 *)

%o (Python)

%o from sympy import isprime

%o def ok(n): return n > 4 and isprime(n-3) and isprime(n+3) and isprime(n+5)

%o print(list(filter(ok, range(6567)))) # _Michael S. Branicky_, Aug 14 2021

%Y Cf. A046138, A087695, A086801, A144840.

%K easy,nonn

%O 1,1

%A _Giovanni Teofilatto_, Sep 22 2008

%E Definition edited and extended by _R. J. Mathar_, Sep 24 2008