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%I #30 Sep 08 2022 08:45:46
%S 23,41,59,131,311,329,581,689,941,1049,1391,1931,2471,2579,2651,3281,
%T 3839,3911,4289,4451,4469,4829,5621,5999,6251,6719,6809,7979,8069,
%U 9761,10391,10589,11021,11759,12011,12389,13559,13919,14369,14801
%N a(n) = 3*A022004(n) + 8.
%C Sum of the members of the n-th prime triple (p, p+2, p+6).
%C All terms are congruent to 5 (mod 18). See A242215. - _Robert Bilinski_, Sep 24 2019
%H Vincenzo Librandi, <a href="/A163635/b163635.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A022004(n) + (A022004(n)+2) + (A022004(n)+6);
%F a(n) = A022004(n) + A073648(n) + A098412(n).
%e 23 is in the sequence because 23 = 5+7+11 = 3*5+8.
%e 41 is in the sequence because 41 = 11+13+17 = 3*11+8.
%t 8 + 3*Select[Prime[Range[1000]], PrimeQ[# + 2] && PrimeQ[# + 6] &] (* _Vincenzo Librandi_, Jan 04 2014 *)
%o (Magma) [(3*p+8): p in PrimesUpTo(1000)| IsPrime(p+6) and IsPrime(p+2)]; // _Vincenzo Librandi_, Jan 06 2018
%o (PARI) is(n)=n%18==5 && isprime(n\3-2) && isprime(n\3) && isprime(n\3+4) \\ _Charles R Greathouse IV_, Jan 06 2018
%Y Cf. A022004, A073648, A098412.
%Y Cf. A242215.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Aug 02 2009
%E Notation normalized by _R. J. Mathar_, Aug 07 2009
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