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A166173
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Digit sum of n-th twin prime pair.
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1
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8, 12, 6, 18, 15, 12, 21, 18, 6, 18, 24, 21, 27, 24, 36, 24, 21, 27, 24, 12, 30, 21, 18, 24, 18, 33, 30, 30, 24, 33, 27, 24, 36, 42, 36, 15, 12, 21, 18, 24, 18, 21, 36, 33, 12, 21, 30, 24, 30, 42, 30, 27, 42, 48, 24, 48, 36, 48, 30, 39, 54, 24, 24, 36, 12
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OFFSET
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1,1
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COMMENTS
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Except for the first term, all the others are multiples of 3.
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LINKS
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FORMULA
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EXAMPLE
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The tenth twin prime pair is 107, 109, so a(10) = 1+0+7+1+0+9 = 18.
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MATHEMATICA
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Total[Flatten[IntegerDigits[#]]]&/@Select[Partition[Prime[Range[400]], 2, 1], #[[2]]- #[[1]]==2&] (* Harvey P. Dale, Dec 03 2016 *)
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CROSSREFS
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KEYWORD
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base,nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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