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%I #18 Jan 03 2020 07:48:57
%S 5,12,25,44,75,118,179,252,355,464,603,754,935,1128,1327,1556,1797,
%T 2068,2351,2664,3013,3434,3867,4330,4853,5424,6025,6644,7287,7948,
%U 8759,9582,10411,11270,12153,13174,14207,15258,16321,17414,18567
%N a(n) = sum of the first n upper twin primes.
%H Amiram Eldar, <a href="/A086168/b086168.txt">Table of n, a(n) for n = 1..10000</a>
%e For n = 4 we have twin prime pairs (3,5) (5,7) (11,13) (17,19) and 5 + 7 + 13 + 19 = 44.
%t lst={};s=0;Do[p=Prime[n];If[PrimeQ[p-2], s+=p;AppendTo[lst, s]], {n, 6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Sep 30 2008 *)
%t Accumulate[Transpose[Select[Partition[Prime[Range[200]],2,1],Last[#]-First[#]==2&]][[2]]] (* _Harvey P. Dale_, Feb 08 2011 *)
%o (PARI) addnexttwin(n)= { s=0; for(x=1,n, if(prime(x+1)-prime(x)==2,s=s+prime(x+1); print1(s",")) ) }
%Y Cf. A006512, A086167.
%K nonn
%O 1,1
%A _Cino Hilliard_, Aug 25 2003
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