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A086168
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a(n) = sum of the first n upper twin primes.
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4
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5, 12, 25, 44, 75, 118, 179, 252, 355, 464, 603, 754, 935, 1128, 1327, 1556, 1797, 2068, 2351, 2664, 3013, 3434, 3867, 4330, 4853, 5424, 6025, 6644, 7287, 7948, 8759, 9582, 10411, 11270, 12153, 13174, 14207, 15258, 16321, 17414, 18567
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OFFSET
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1,1
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LINKS
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EXAMPLE
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For n = 4 we have twin prime pairs (3,5) (5,7) (11,13) (17,19) and 5 + 7 + 13 + 19 = 44.
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MATHEMATICA
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Accumulate[Transpose[Select[Partition[Prime[Range[200]], 2, 1], Last[#]-First[#]==2&]][[2]]] (* Harvey P. Dale, Feb 08 2011 *)
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PROG
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(PARI) addnexttwin(n)= { s=0; for(x=1, n, if(prime(x+1)-prime(x)==2, s=s+prime(x+1); print1(s", ")) ) }
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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