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Search: id:A103818
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| A103818 |
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Primes p such that p and p+2 are twin primes, and also the strings 987654321p and 987654321p+2 are twin primes. |
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+0
1
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| 569, 1019, 2267, 2801, 3917, 5879, 8231, 8999, 18917, 19139, 25301, 26111, 27281, 30089, 40127, 42071, 43319, 53279, 55337, 57527, 75539, 80747, 84317, 103991, 106961, 117701, 149519, 154157, 154871, 156491, 159347, 160709, 201827, 208589
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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569 and 571 are twin primes, also 987654321569 and 987654321571 are twin primes
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MATHEMATICA
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fQ[n_] := Block[{p = IntegerDigits[n], q = IntegerDigits[n + 2], r = {9, 8, 7, 6, 5, 4, 3, 2, 1}}, If[ PrimeQ[n + 2] && PrimeQ[ FromDigits[ Join[r, p]]] && PrimeQ[ FromDigits[ Join[r, q]]], True, False]]; Select[ Prime[ Range[ 19400]], fQ[ # ] &] (from Robert G. Wilson v Mar 30 2005)
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CROSSREFS
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Sequence in context: A023099 A087424 A142818 this_sequence A097035 A074907 A073036
Adjacent sequences: A103815 A103816 A103817 this_sequence A103819 A103820 A103821
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KEYWORD
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nonn,base
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), Mar 30 2005
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EXTENSIONS
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More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 30 2005
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