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Primes which are the sum of a twin prime pair + 1.
5

%I #38 Feb 24 2024 01:15:03

%S 13,37,61,277,397,457,541,1201,1237,1321,1621,1657,2557,2857,3217,

%T 4057,4177,4261,4621,5101,5581,6337,6661,6781,7057,7537,8101,8317,

%U 8461,8521,8677,9277,9601,10837,10957,11317,11701,12541,12601,12721,13381,13921

%N Primes which are the sum of a twin prime pair + 1.

%H Amiram Eldar, <a href="/A118071/b118071.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harvey P. Dale)

%F {A001359(k) + A006512(k) + 1} INTERSECT {A000040}.

%F {A054735(k) + 1} INTERSECT {A000040}.

%F {2*A001359(k) + 3} INTERSECT {A000040}.

%F {2*A006512(k) - 1} INTERSECT {A000040}. - _Juri-Stepan Gerasimov_, Apr 26 2010

%e a(1) = 13 = 5 + 7 + 1 where (5,7) is a twin prime pair.

%e a(2) = 37 = 17 + 19 + 1.

%e a(3) = 61 = 29 + 31 + 1.

%e a(4) = 277 = 137 + 139 + 1.

%e a(5) = 397 = 197 + 199 + 1.

%t Select[Total/@Select[Partition[Prime[Range[1000]],2,1],#[[2]]-#[[1]] == 2&]+1,PrimeQ] (* _Harvey P. Dale_, Jul 25 2019 *)

%o (PARI) is(n)=n%12==1 && isprime(n) && isprime(n\2-1) && isprime(n\2+1) \\ _Charles R Greathouse IV_, Jan 21 2015

%Y Cf. A000040, A001359, A006512, A054735.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, May 11 2006

%E More terms added by _Vladimir Joseph Stephan Orlovsky_, Mar 10 2009