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Primes p such that p-2 is not a prime.
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%I #37 Sep 08 2022 08:44:49

%S 2,3,11,17,23,29,37,41,47,53,59,67,71,79,83,89,97,101,107,113,127,131,

%T 137,149,157,163,167,173,179,191,197,211,223,227,233,239,251,257,263,

%U 269,277,281,293,307,311,317,331,337,347,353,359,367,373,379,383,389,397,401

%N Primes p such that p-2 is not a prime.

%C Primes p (for p>=11) such that sigma(p-2) > p. - _Benoit Cloitre_, Feb 08 2002

%C Prime numbers that are not the sum of two smaller prime numbers. - _Tomas Xordan_, May 10 2007

%H Vincenzo Librandi, <a href="/A025584/b025584.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) ~ n log n. - _Charles R Greathouse IV_, Jan 10 2013

%t Select[ Prime /@ Range[100], ! PrimeQ[# - 2] &] (* _Jean-François Alcover_, Apr 19 2013 *)

%o (Magma) [p: p in PrimesUpTo(420) | not IsPrime(p-2)]; // _Vincenzo Librandi_, Jul 26 2013

%o (PARI) lista(nn) = forprime(p=2, nn, if (!isprime(p-2), print1(p, ", "));); \\ _Michel Marcus_, Dec 05 2015

%Y Complement of A006512 in A000040.

%Y Cf. A014092.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_.

%E Better description from _Vladeta Jovovic_, Dec 14 2002